The Blues took a two-goal lead into the break following a flat first half, with Demba Ba and Eden Hazard grabbing goals for the hosts.
You can read how events unfolded at Stamford Bridge with Sports Mole's minute-by-minute coverage below.
Good evening! Thank you for joining Sports Mole for tonight's match at Stamford Bridge between Chelsea and Southampton!
Tonight's match, as most matches from now on will be, is a huge one if Chelsea still harbour any thoughts of getting back into the title race. A win in this, their game in hand over the two Manchester clubs, will put them to within four points of City and 11 points behind United.
As things stand, Chelsea sit third in the Premier League table, but fourth-placed Tottenham Hotspur are just one point behind them. Perhaps just as important as closing the gap on the Manchester clubs, then, is to distance themselves from the chasing pack.
The match is also a big one for Southampton, who boosted their chances of Premier League survival with their win over Aston Villa at the weekend.
The Saints are now sitting relatively pretty in 15th place, although they are only two points clear of the bottom three and will not be fancied to get anything in their game in hand tonight.
That's not to say that they won't get something from tonight's game, however. QPR came to Stamford Bridge and pulled off the shock of the season so far by winning 1-0, and Southampton will be dreaming of a similar result tonight.
Chelsea have bounced back from that defeat in style, though. Since Shaun Wright-Phillips struck for the league's bottom side they have thrashed both Southampton and Stoke, the latter ending the Potters' unbeaten home record in the league this season in emphatic fashion.
We'll have a more in-depth look at the 5-1 match between these two sides 11 days ago in a bit, but first I think it's about time to bring you some team news!
Well, the headline news from the Chelsea camp is that Demba Ba retains his place in the side, with Fernando Torres left on the bench yet again. There are two changes for the Blues as Gary Cahill and Oscar come in for Branislav Ivanovic and Ryan Bertrand.
CHELSEA STARTING XI: Cech; Azpilicueta, Cahill, Luiz, Cole; Ramires, Lampard; Oscar, Mata, Hazard; Ba
Southampton have made a couple of changes of their own, most notably dropping Rickie Lambert and Gaston Ramirez to the bench in favour of Steven Davis and Guly do Prado.
SOUTHAMPTON STARTING XI: Boruc; Clyne, Yoshida, Hooiveld, Shaw; S. Davis, Schneiderlin, Cork, Puncheon; Guly, Rodriguez
So, what do you think of those teams? It is interesting that Benitez has stuck with Ba up front. He seems to have established himself as the first choice striker in double-quick time, and Torres can't be happy about missing out again. Juan Mata is probably the man Southampton will be most worried about as the Spaniard has the ability to pull the strings from midfield if they allow him too much space.
Nigel Adkins has also made an interesting attacking decision by dropping Lambert. The striker has been Southampton's biggest goal threat this season, but perhaps Adkins wants a player who is more likely to track back when needed in a match that will presumably see the Saints on the back foot for much of it.
Jay Rodriguez is the man who gets the nod ahead of Lambert, perhaps because the former scored the Saints' only goal when the two sides met in the FA Cup 11 days ago?
While we're on the subject of that match, let's have a closer look at what exactly transpired when these two met...
Well, the simple answer is that Chelsea dominated. Southampton dared to dream of knocking the current FA Cup holders out of the competition at the first hurdle when they took the lead, but the Blues responded and eventually ran out comfortable 5-1 winners. The game was especially notable for Ba's debut double for the Blues, wasting no time in getting his Chelsea tally underway.
So that's the very recent history between the two sides, how about matches beyond that? Well, it doesn't make much better reading for Southampton fans. They haven't beaten the Blues since the New Year's Eve in 2001 and have lost their last five meetings.
Even more worringly, it is almost 13 years since Southampton triumped on this ground. Overall, the clubs have played 59 times, with Chelsea winning 27 and Southampton 17.
The Saints' away record so far this season isn't too daunting either. Only three teams have amassed less points on their travels than Adkins's men, who have claimed just eight points from 10 away games.
They may be able to take some solace in the fact that Chelsea's home record is far from perfect, however. The Blues have been significantly better away from home than at Stamford Bridge this season, picking up just 18 points in West London so far this season.
There is no getting away from the fact that Chelsea are overwhelming favourites tonight, though. If Southampton get anything from this one then it would be a big shock. QPR's win here a couple of weeks ago showed that anything was possible, however, so Southampton will know that they do stand some sort of chance.
This isn't the only match on tonight, remember. There are also a couple of mouth-watering FA Cup third round replays as Arsenal take on Swansea and Manchester United host West Ham. I'll try to keep you updated with any goals from both those matches.
Whenever Chelsea play at the moment there seems to be some sort of circus surrounding them. Be it Torres's form or the fans' displeasure with Benitez, there always seems to be a sub-plot with them. The latest is Frank Lampard's transfer saga, with the club looking set to allow the England international to leave at the end of the season.
Many people have been left bemused by this decision, with Lampard looking as good as ever and the likes of Paul Scholes and Ryan Giggs at Manchester United proving that age is not an issue for some players.
However, Chelsea have a strict club rule regarding 'over-age' players which they don't seem willing to change for anyone. Didier Drogba was let go for the same reason having just scored the penalty that gave the club their first ever Champions League! If he does leave, though, what a servant he has been. He is edging closer to the club's all-time scoring record, and I for one hope he breaks it before his time ends.
Right, we have 10 minutes until kickoff, which can mean only one thing - prediction time! I can't see anything other than a home win tonight. Chelsea are prone to the odd poor performance but, in general, under Benitez they have dispatched of 'lesser' teams with realtive ease. I'm going for a 3-0 win to Chelsea.
How big would a Southampton win be though?! It wouldn't propel them up the table in terms of positions, but it would take them five points clear of the bottom three - a big lead when it is so tight down there.
Chelsea, meanwhile, simply must win to stand any chance of staying remotely in the title race.
The big football news from earlier in the day - Pep Guardiola agreeing to join Bayern Munich - may have repercussions at Stamford Bridge. The former Barca boss had been the favourite to take over from Benitez, but could the current manager stay beyond the season and shed his 'interim' tag after today's news?
Ba scored twice on his club debut against Southampton 11 days ago and tonight makes his full home debut. He will be hoping for another debut double.
The teams are out and we're about to get underway...
Here we go! Southampton kick us off tonight and immediately go out on the attack but Rodriguez's pass is misplaced.
Schneiderlin bundles Ramires over in the middle and comes away with the ball. The ref doesn't blow, correctly, but Southampton don't take advantage of what looked like a promising counter attack.
It is the visitors who are enjoying the majority of the ball in these very early stages. Good start from the Saints.
SHOT! Just as I say that, Chelsea break away and have a clear sight of goal. Ba collects it on the left and passes it across the edge of the box to Mata, who tees up Oscar but the Brazilian can only pull his shot wide.
A brilliantly disguised ball from David Luiz finds its way to Hazard in the box, but his pullback towards Ba is cleared away. Chelsea are growing into this one now and it's beginning to take a more familiar form.
CLOSE! Ramires breaks free in the middle before feeding Ba, whose pass across the face of goal is left by Hazard and almost turned into his own net by a Southampton defender!
Luiz pings another ball out to Mata, who sends it back across towards Lampard. The England international looks like he will rise to meet it, but in the end leaves it for anyone coming in behind him - there's no-one there though!
Luiz is spraying balls left, right and centre at the moment. This one goes down the middle to Mata in the box, but for once the midfielder's first touch lets him down and the ball goes out for a throw-in.
SHOT! Hazard has a half-chance to break away and he tries to work space to shoot on his right. In the end he passes it across to Lampard, who in turn moves it on Azpilicueta who blazes his shot high and wide.
CHANCE! Oh that's a better chance than Puncheon made it look. The winger rises higher than Cole to meet a cross in the box, but his header goes a long way wide when you'd have expected him to test the keeper.
Demba Ba swings a leg at a bobbling ball on the edge of the box, but he doesn't get hold of it and it trickles through to Boruc. Still waiting for our first big chance of this match.
Yoshida does his keeper no favours with an over-zealous backpass which he has to chest down on his own line before clearing it only as far as Mata. Southampton recover and win the ball back, however.
Chelsea knock the ball about at the back for over a minute and when they finally try and go forward they lose it! Southampton can't take advantage, though, and Chelsea win the ball back straight away. It's been a slow start to this one.
GOAL! Chelsea 1-0 Southampton (Demba Ba)
A quiet Stamford Bridge suddenly explodes to the sound of a goal! Southampton carelessly give the ball away to Lampard, who plays it back to Azpilicueta. The full-backs cross is deflected into the path of Ba, who swivels and hits a first-time strike into the bottom corner. It's his first league goal for the club, and he's scored against Southampton again!
There's a very subdued atmosphere at Stamford Bridge tonight, even after that goal. Very little of this match has been played in the opposition's final third so far, so there's not much to get excited about for the fans.
Southampton have a corner now, though. Puncheon's free kick is cleared away before Hazard puts it out for a corner. Guly's set piece is poor, however, failing to beat the first man.
The Saints have their best move of the match, knocking the ball about on the edge of the Chelsea penalty area, but the final pass is just too heavy for Puncheon to latch on to.
Interestingly, Southampton have enjoyed the lion's share of possession since going behind. The last five minutes have seen them have 59% of the ball, unusual away from home especially against a team like Chelsea.
CHANCE! Southampton look in control of the ball now. Yoshida's long ball forward is brilliantly controlled by Rodriguez in the box, who then lays it off to Davis. The midfielder's should do much better with his shot, however, as he drags it wide.
It's surprised to see how this match is panning out. In recent weeks Chelsea have put sides to the sword when they've gone ahead, but here they seem content to let Southampton have all of the ball. If you didn't know who was who, you'd guess that Southampton were the home team at the moment!
Just a hint of an opening for Chelsea as Mata lobs the ball forward towards Ba, who has beaten the offside trap. Boruc is out quickly to clear the ball into the stands, however. Good goalkeeping.
Another half-chance for the hosts! Ba is involved again, feeding Hazard who in turn gives the ball to Lampard, but the England international just can't get the ball out from under his feet and his eventual shot is blocked.
CHANCE! Mata gets the ball inside the penalty area but, like Lampard before him, he gets it stuck under his feet. Eventually he plays it back to Lampard, who fluffs his shot wide. When the ball falls to Lampard on the edge of the box you expect to see the ball nestling in the net!
GOAL! Chelsea 2-0 Southampton (Eden Hazard)
Chelsea have ended this half very strongly! A scramble in the penalty box results in the ball falling back to Ramires, who smashes a half-volley against the woodwork. The ball bounced back out to the edge of the box, where Hazard is on hand to control a volley into the corner.
HALF TIME: Chelsea 2-0 Southampton
There's the half-time whistle and most of the half's action came in the closing moments there! Demba Ba scored his first goal at Stamford Bridge with a good volley to put the Blues ahead, but Southampton came back and dominated possession for a while after.
However, Chelsea came to life at the end of the half, having a few decent openings before Hazard doubled his side's lead right on the stroke of half time. Not a classic by any means so far, but the end to the first 45 provides cause for optimism.
Southampton looked like the more assured team in possession after Chelsea's first, but they couldn't do anything with the ball. Davis has had their best chance of the match so far, but he squandered is and the Saints are still yet to test Petr Cech.
Let's have some stats from that first half then, shall we? Chelsea have had 10 shots, six of which have been on target compared to Southampton's three shots, with none on target.
The sides have both shared 50% of the possession, but Chelsea have done more with it than Southampton managed. It's a long way back for the visitors now.
Right, the teams are coming back out onto the field of play. What will their respective managers have had to say? Well, for Chelsea it will be more of the same. They haven't set the world alight so far but their performance has been effective.
For Adkins, he will be imploring his side to create more when going forward. They've had the possession to do so, just not the creativity.
Chelsea get us back underway.
A positive start from Chelsea as Ashley Cole finds himself in an advanced position. He looks to be in two minds, though, and his shot/cross is easy for Boruc.
Ba then tries to find Oscar in the box with a curling pass, but it is too close to Boruc who collects again. One thing Chelsea have been good at so far this season is pushing on when leading at half time, and they look to be in the mood to do so again here.
Saying that, they have resorted to knocking the ball about patiently again as they probe for an opening in the Saints' defence.
Southampton have a freekick in a good position as Schneiderlin is felled by Oscar. Guly's ball in is horribly over-hit, however, and another decent chance for Southampton is wasted. They need to make the most of them as it is probably their most likely source of a goal in this one.
A rare ripple of noise spreads around Stamford Bridge, and Chelsea respond by sending Mata through on goal, but the Spaniard is offside.
SOUTHAMPTON SUB: The first change of the day sees Rickie Lambert replacing Jay Rodriguez. A positive move from Adkins to bring on the club's top scorer.
GOAL! Chelsea 2-1 Southampton (Rickie Lambert)
Southampton fans will be asking why Lambert wasn't in from the start! Clyne bundles his way down the right flank and puts a cross in to the box, which Lambert meets before sending a fine header into the top corner. Game on!
Half chance from Chelsea as Mata slips the ball to Hazard, but the Belgian just can't bring it under his spell inside the box. That Southampton goal is exactly what this game needed.
Southampton are knocking on the door too now. They look much more dangerous with Lambert up front and there's been a noticeable increase in crosses into the box.
Chelsea break with pace down the left and Hazard tries to thread a pass through to Oscar but Southampton clear it away. The Saints need to push forward for another, but they also must be wary of the threat that the hosts pose on the counter attack.
Hazard threatens again down the left, this time latching on to another fine Luiz pass before pulling the ball back to Cole, whose shot is blocked.
SOUTHAMPTON SUB: On comes Chaplow for Davis, and Adkins will be hopeful that this sub has a similar impact to his first one!
CHANCE! Echoes of Zola and Poyet there! Mata sends a perfectly-weighted pass over the top to Ba, who tries an acrobatic volley which goes over the top. He perhaps should have done better, but those chances are never easy.
The game is getting nice and open now. Mata links up with Hazard, getting the ball back before being felled right on the edge of the box by Yoshida. Good shooting opportunity from this free kick.
Before that happens, though, Mata will receive treatment. He looks in genuine pain but Yoshida's challenge seemed fairly innocuous.
CLOSE! Lampard's free kick flies just wide of the post. Boruc was rooted to the spot, there was no way that he was getting to that one if it was on target.
Mata is back on the field and, while he's not moving completely freely just yet, he will be able to continue.
SOUTHAMPTON SUB: Southampton's record signing Gaston Ramirez enters the field of play, replacing Guly do Prado.
GOAL! Chelsea 2-2 Southampton (Jason Puncheon)
What a goal! Southampton are level! Shaw leaves Azpilicueta in his dust with a powerful run down the left before putting the across the box. It's behind Ramirez but falls to Puncheon, whose first touch loops the ball in the air allowing him to lash it past Cech on the volley. Great comeback from the Saints.
The Saints have shown great spirit to come back here, and suddenly Chelsea, who looked destined to cruise to victory at half time, need another goal.
CHELSEA SUB: Benitez's reaction is to bring off Frank Lampard, much to the distaste of the Chelsea fans, and on comes Torres in his place. Torres and Ba will now play up front together, it'll be interesting to see how that develops.
In fact, it looks like Torres has started out wide on the right. Not sure about that one I have to say.
Mata and Torres link up on the right and the latter wins a corner off his marker, but Mata's set piece is cleared with ease.
Demba Ba takes the ball down on his chest brilliantly before swivelling and volleying towards goal. His shot is blocked, but that was good play from the striker.
YELLOW CARD! David Luiz becomes the first player to enter the referee's notebook tonight after blocking off Ramirez's run. Michael Oliver is not falling for his innocent face.
CHANCE! Torres has moved into the middle now and he has a good chance to regain Chelsea's lead. Mata finds him bursting through the middle in acres of space. He advances towards the box, beats his man but can only fire his shot wide. He really should've done better with his finish there.
Ramirez tries to run Azpilicueta inside out but the young defender is having none of it and is eventually awarded a free kick for a silly foul by the Saints player. That's not the first he's done since coming on.
FA CUP UPDATE: A quick update from the FA Cup third round replays going on tonight. Arsenal have progressed with a 1-0 win over Swansea, while Manchester United lead West Ham 1-0.
Back to Stamford Bridge, though, and Southampton are on the verge of securing a huge point.
PENALTY SHOUT! The hosts want a penalty as Cahill goes down in the box. The ref is having none of it, though, and now Southampton have a free kick in a good crossing position...
...but Ramirez tries to take it quickly and it comes to nothing.
We will have four minutes of added time here, will they provide any late drama?
The Chelsea fans aren't happy as Torres over-hits a cross aimed towards Ba. Their edging ever closer to yet more dropped points at home.
Chelsea are pumping the ball forward now, but Cole is caught offside and this one could be all over.
FULL TIME: Chelsea 2-2 Southampton
A chorus of boos greet the full-time whistle as Chelsea squander a two-goal lead against struggling Southampton, continuing their woes at Stamford Bridge. They have won just two of their last eight matches at home.
At half time there seemed to be no way back for a Southampton side who looked devoid of any ideas or creativity. However, the introduction of Rickie Lambert made a big difference and he set the Saints on their way to a fine comeback.
Benitez, meanwhile, will still be wondering how his side can be so hit and miss at time this season. They thrashed Southampton 5-1 11 days ago, but on their own turf they couls only manage a draw tonight. They are lacking consistency at the moment and are now almost certainly out of the title race.
Right, that's all from me tonight! Thanks for joining Sports Mole for this evening's match and I leave you with Sian Cowper's match report. Be sure to stick around from reaction to this one as well as match analysis, which will be on the site within half an hour. Good night!