Eden Hazard levelled from the spot within four minutes after winning a controversial penalty, though, and Marcos Alonso looked to have sealed a come-from-behind victory for the visitors when he tucked home just six minutes from time.
However, an enthralling contest had one final twist in the tale when Bellerin's late strike restored parity once again.
Find out how all of the action unfolded courtesy of Sports Mole's live minute-by-minute updates below.
Seven points and three places separate these two sides in the table as things stand, and this is a fixture which has gone a long way towards shaping both of these team's seasons over the past year-and-a-half. Tonight could prove to be pivotal again, with defeat for Arsenal leaving them playing serious catch-up in the top-four race.
We will have a closer look at both teams in a short while, but first let's check out the team news from North London...
Well, the headline news as far as the home side are concerned is that Mesut Ozil returns to the starting lineup having missed the New Year's Eve draw with West Bromwich Albion due to a minor knee problem.
The relentless speculation over his future is only likely to intensify this month now that he is able to discuss terms with other clubs, but having been a major doubt for this evening's game he has indeed recovered in time for start. The German may not be at the Emirates for much longer, but he is still a key part of this team.
Sanchez's attitude and workrate have been questioned at time this season, and there has even been talk of it causing a rift in the squad, but the Chilean has started showing some of his best form in recent weeks and, after scoring a brace against Crystal Palace recently, it was his free kick which forced the own goal against West Brom last time out too.
He may be dividing opinion between fans at the moment, but there is no doubt that Arsenal will miss Sanchez whenever he leaves.
In fairness to the Gunners, they have been hit badly by injuries recently. Sead Kolasinac and Laurent Koscielny - two almost guaranteed starters in the first team - joined the likes of Ramsey, Giroud, Monreal and Cazorla on the injury list against West Brom, leaving Wenger with a rather makeshift and inexperienced defensive line tonight.
Elsewhere there is another start for Jack Wilshere - his sixth in a row to make it his longest Premier League starting streak for Arsenal since October 2013 - while Holding and Maitland-Niles come in as the only two changes from the West Brom draw.
Hazard scored a memorable solo goal when these two sides met last season so Arsenal will know all about the threats he poses, and today he is expected to once again start in a free role slightly off Alvaro Morata.
Fabregas, like Hazard, was rested against Stoke, but he is very much an important part of Conte's first-team plans now having at one stage looked like he was close to leaving. Arsenal will need no reminding about the ability he has to unlock defences.
Indeed, Drinkwater is not the only player who impressed last time out but is not included today, with all five goalscorers from that match left on the bench this evening. Zappacosta also started the Stoke game on the bench, but Rudiger, Drinkwater, Willian and Pedro all drop out.
At the other end of the field Alvaro Morata leads the line once again for Chelsea having scored 10 goals so far this season, six of which have come with his head.
Wenger and his players were left incensed by Mike Dean's decision to award the Baggies a penalty in the dying stages at The Hawthorns, allowing the hosts to rescue a point in the 89th minute. The penalty itself was a hugely controversial call - widely deemed to be a wrong one by most observes - yet Wenger was still charged with alleged using abusive language towards a match official by the FA yesterday.
However, the Gunners are six points and two places worse off than they were at the same stage of last season and sit six points adrift of the Champions League places heading into the New Year. A win tonight would lift them back above tottenham, but that could only be temporary until Spurs face West Ham United tomorrow.
The Gunners won just two of their seven Premier League games last month, drawing four and losing one whilst conceding 11 goals and scoring just 10. That said, they also come into this match on an eight-game unbeaten streak across all competitions including six in the Premier League, which is their longest run since December 2016.
These matches in particular have proven to be costly for Arsenal this season, having conceded at least three goals in four of their six league matches against other teams that finished in the top six last season, although the reverse fixture with Chelsea was one of the two exceptions to that.
That run stretches back to Bayern Munich's visit in March and includes 17 Premier League outings here, during which time they have won 14, drawn two and lost just that one to picked up 44 points from the 51 on offer.
Even so, only Manchester City boast a better points-per-game ratio in front of their own fans this season, while the league leaders are also the only team to have treated their home fans to more goals too.
There is a similar disparity when it comes to Arsenal's defensive efforts too. Wenger side have kept clean sheets from their 10 home league games this season, compared to just three from 11 outings on the road. Arsenal have also scored in 24 consecutive home Premier League games stretching back to October 2016.
However the Blues have only won one of their last four away games in the Premier League, taking five points from a possible 12 in that time, and in all competitions their form has been mixed with four wins and three defeats from their last nine.
Chelsea immediately went on a 13-match winning run - the joint-longest in a single season before this term - and the switch has been so successful that pretty much every manager in the division has experimented with it since.
That could be the case again this time around with Arsenal having already lifted the Community Shield at Chelsea's expense and this two set to come up against each other another three times in the next three weeks courtesy of being drawn against each other in the EFL Cup semi-finals.
Manchester City look like being out of reach, but the race for a top-four spot is far from over as Chelsea would move temporarily eight points clear of fifth place with a win tonight too - not to mention 10 clear of sixth-placed Arsenal.
The champions certainly come into this match in good form, though, winning four of their last five Premier League games and taking 13 points from a possible 15 in the process.
That includes a six-game unbeaten streak heading into this match, with Chelsea also keeping four clean sheets in that time.
At the other end, though, the Blues have failed to score in two of their last three Premier League away games, while they could lose three successive top-flight London derbies for the first time since October to December 2001, when the third defeat was inflicted by Arsenal.
The stats point to this being a fairly low scoring affair, and with Arsenal good at home and Chelsea good away, that adds another level on intrigue onto the game. However, Arsenal are missing a number of key players in defence and midfield so I am backing Chelsea to come out on top.
SPORTS MOLE SAYS: Arsenal 1-2 Chelsea
Chelsea have won seven in that time, and their 3-0 loss here last term also ended a five-match unbeaten streak at the Emirates in the Premier League.
The last time Arsenal didn't lose either Premier League meeting with Chelsea in a season was 2011-12, while the last time they kept a clean sheet in both meetings was 1998-99.
The Gunners have been aided by red cards in all of those games though, with Chelsea having had a man sent off in each. Indeed, there have been six red cards in the last seven meetings between these two sides across all competitions.
ARSENAL STARTING XI: Cech; Chambers, Mustafi, Holding; Bellerin, Xhaka, Wilshere; Maitland-Niles; Ozil, Lacazette, Sanchez
CHELSEA STARTING XI: Courtois; Azpilicueta, Christensen, Cahill; Moses, Kante, Bakayoko, Fabregas, Alonso; Hazard; Morata
Both sides have seen glorious chances wasted by some of their best players in an open and attacking contest, and if the same happens in the second half then it is difficult to see this one ending 0-0.
Morata almost got on the end of a low Moses cross moments later while Bakayoko had also drawn a save from Cech with a really good chance. Fabregas wasted another right on the stroke of half time too, blazing his finish off target after some delicious play by Hazard.
The closest the hosts have come was when Sanchez poked an effort towards goal from inside the box which Courtois got a stunning hand to. The Belgian turned the ball against the inside of one post and them watched as it trickled across the line and struck the other, when he was finally able to drop on it.
The concern for Arsenal may be that they have seen their best openings go begging, but both sides will go into this second half confident that they can come away with all three points after that first-half display.
DOUBLE SAVE! Cech denies Hazard with his feet before getting up to push away Alonso's header!— Sky Sports PL (@SkySportsPL) January 3, 2018
Watch live on Sky Sports Premier League or follow in-game clips and highlights here: https://t.co/Qn87fWuLmU https://t.co/ecKU1ScrGf
Holding's pass takes a nick off Morata on the way through which only takes it into the path of Wilshere, who lashes an unstoppable effort past Courtois at his near post.
Hazard sees an initial cross blocked, but as Bellerin swings at the loose ball Hazard just beats him to it. The Belgian goes down theatrically despite there not being a huge amount of contact, but Anthony Taylor points to the spot.
Hazard steps up himself and fires his spot kick straight down the middle.
4 - Arsenal have conceded a joint-high 4 penalty goals in the Premier League this season (level with Watford and West Ham). Spotted. pic.twitter.com/QiBTWEwYwB— OptaJoe (@OptaJoe) January 3, 2018
Willian sends a fine cross-field ball out to Zappacosta, who turns past a tiring Maitland-Niles before drilling a low cross into the box. It is not Morata or Willian in there, but Alonso getting in front of his man at the near post to steer a really good finish past Cech.
Arsenal just keep serving up these thrillers in these big games at the moment and, while they aren't getting as many points from them as they might like, it is certainly good for the neutral!
This one was a thrilling, end-to-end contest from the first whistle until the last, with Hector Bellerin eventually rescuing a point in stoppage time after Marcos Alonso had seemingly wrapped up the win for chelsea. Incredible match.
Thank you very much for joining Sports Mole for tonight's incredible contest as Arsenal and Chelsea ultimately share the spoils in a four-goal thriller at the Emirates. I will leave you with our action-packed match report, and be sure to stick around for reaction too.
From me, though, it is goodbye for now!