The result means that Sparta need to match the 0-1 result or score twice at Stamford Bridge in the return leg to stand any chance of progressing.
You can read how the match unfolded with Sports Mole's play-by-play updates below.
5pmGood afternoon and happy Valentine's Day to everyone! Thank you very much for joining Sports Mole for today's Europa League tie between Sparta Prague and Chelsea.
5.02pmTEAM NEWS: Let's get straight down to business and bring you some team news! The big story coming out of Chelsea is that Fernando Torres starts, as expected. Marko Marin also comes into the starting lineup, while the ever-dependable Frank Lampard remains alongside Ramires in the centre of midfield.
5.04pmSPARTA PRAGUE STARTING XI: Vaclik; Zapotocny, Hybs, Svedjik, Vacha; Matejovsky, Holek, Husbauer, Krejci; Lafata Kadlec
5.05pmSPARTA PRAGUE SUBS: Cech, Pamic, Kweuke, Vidlicka, Polom, Janos, Bednar
5.06pmCHELSEA STARTING XI: Cech; Azpilicueta, Ivanovic, Cahill, Bertrand; Ramires, Lampard; Marin, Mata, Hazard; Torres
5.08pmSo Rafael Benitez has named a strong lineup for this one. Demba Ba was not available to him as he is cup-tied, so Torres starts up front. There are some regular starters on the bench, namely John Terry, Ashley Cole and Oscar, who Benitez could bring on if he needs some experience or a 'plan B' at any point. Overall, though, his team selection suggests that he is taking this competition seriously.
5.10pmIt is also worth noting that Branislav Ivanovic will make his 200th appearance for the Blues today. He has become a vital part of the Chelsea set-up in that time and has already established himself as a great servant to the club.
5.12pmAn even better servant to the club in Frank Lampard. He is consistently edging ever closer to Bobby Tambling's all-time goalscoring record for the club, but still hasn't been offered a new contract at Stamford Bridge. Like the consummate professional he is, he has just put his head down and played as good as ever, and I don't expect anything different today.
5.14pmAs for the hosts, I suspect that the majority of the Sparta side will be unfamiliar to a number of people, although you may recognise Marek Matejovsky and Roman Bednar, who have enjoyed spells at Reading and West Brom respectively. Bednar has also played for Leicester, Blackpool and Hearts in Britain, so he will be keen to get on to remind English audiences what he can do.
5.16pmThe biggest threat to Chelsea's defence this afternoon will probably be Vaclav Kadlec, who has netted five times in 12 appearances so far this season. His partner up front today, David Lafata, is making his first appearance of the season.
5.18pmSparta also have goalscoring ability on the bench, with Leonard Kweuke matching Kadlec's tally of five goals in 12 games. Incidentally, Kweuke is just one of two players not from the Czech Republic in the Sparta squad, alongside Croat Manuel Pamic. Compare that with the 10 different nationalities in the Chelsea squad and you have some idea of the gulf in financial reach between these two sides.
5.20pmToday is a particularly special day for Chelsea goalkeeper Petr Cech, who spent a year at Sparta before moving on to Rennes and then Chelsea.
5.22pmOther notable former Sparta Prague players include the likes of Pavel Nedved, Tomas Rosicky, Karel Poborsky, Patrick Berger and Jan Koller, so they have certainly provided us with a number of good players in the past.
5.24pmThey are also the most successful Czech club ever, having won the league a staggering 35 times, going back to the days of Czechoslovakia. They currently sit third in their domestic league table, however, three points off first-place Viktoria Plzen.
5.26pmInterestingly, these two sides' form over the last five games has been identical. Three consecutive draws were followed by a loss and then a win, although a winter break means that this is Sparta's first competitive game since December 6.
5.28pmThis match will be Sparta's 10th in the Europa League so far this season, and only Lyon have managed to beat them so far. Chelsea, meanwhile, will be appearing for the first time having been dumped unceremoniously out of the Champions League.
5.30pmChelsea's last appearance at this level - the UEFA Cup - ended in disappointing fashion as they were beaten by Viking 5-4 on aggregate way back in 2002.
5.32pmA tough match lies ahead for the Blues, then, but will Benitez be able to overcome it? The pressure on him since he took the job has been relentless, and you feel that even a trophy wouldn't save him now.
5.34pmHowever, Benitez forged a formidable reputation for himself as one of the best cup managers going while at Liverpool and, although the Champions League is no longer a possibility, he had an impressive record in Europe. He reached two Champions League finals with Liverpool, remember, and won the first with arguably the worst side ever to win that trophy!
5.36pmSpeaking of Liverpool, Benitez's former club are currently in action against Zenit St Petersburg, and there will be a number of other British clubs playing tonight. I will keep you updated as the goals (hopefully) fly in across Europe.
5.38pmBenitez has urged his team to be 100% focused on tonight's game. He is certainly taking this trophy seriously and rightly so. Most of his other chances of silverware have evaporated, making this one even more important.
5.40pmHis skipper, John Terry, has echoed these thoughts. He insists that Chelsea want to win the Europa League this season despite being embroiled in a battle for a top four place in the Premier League.
5.42pmMeanwhile, Sparta keeper Tomas Vaclik believes that his side will have to be at their very best to overcome Chelsea over two legs, but is confident of avoiding defeat in today's game.
5.45pmVaclik has reason to be confident. Sparta are unbeaten at home in Europe for 11 games, a run that stretches all the way back to the 2010-11 season. The Generali Arena has become something of a fortress for them.
5.48pmChelsea will be quietly confident of breaking that record, however. They will know that this is by no means an easy place to go, but they also know that they have more strength and depth in their squad. Even so, a draw wouldn't be a bad result for the Blues.
5.50pmPREDICTION: There are 10 minutes until kickoff, which means that it is time for the match prediction! I can see this being quite a tight, close game. Chelsea have the superior quality, but Sparta's home advantage could also prove decisive. I'm going to go for a 1-1 draw.
5.53pmSparta are not just impressive at home in Europe. Domestically, they have lost just one of their last 15 games in front of their own fans.
5.57pmHow is Chelsea's away record in Europe, though? Well, not great to be honest. They have lost their last two and have win two of their last 11.
6pmRight, the players are out on the pitch and we're about to get going here!
0 minHere we go! The fans from both sides are in good voice as we get underway here in Prague.
2 minHazard shows an early sign of his quick footwork, darting to the edge of the box before being stopped by a defender. He wants a free kick but the ref waves his claims away.
3 minSHOT! Hazard lays the ball off to Lampard, who tries to guide a trademark effort into the corner, but Vaclik gets down well to save. Lampard has an uncanny knack for getting the ball to bounce just in front of the keeper, making it harder for them to collect.
5 minMata slides an almost-perfect ball behind the defence towards Torres, but a defender just slides and gets a foot in to deny the Chelsea striker. The visitors are dominating the early exchanges here.
6 minSparta's first foray forward results in Cahill being forced to play the ball out for a throw-in. Chelsea win it back almost immediately, however, and come forward again.
7 minCHANCE! Chelsea hit Sparta on the counter and almost find an opener. Marin attacks the defender before laying it off to the overlapping Hazard. The Belgian's cross flashes across the face of goal, with no-one waiting for what would've been a simple tap-in at the back post.
8 minMarin again runs straight at the defender, this time Zapotocny, who can't cope with the wingers speed and brings him down. The resulting free kick is cleared and Ramires hits a shot well wide from about 25 yards out.
10 minHazard again flashes a cross into the fabled corridor of uncertainty, but again there is no Chelsea player attacking it. The trio of Marin, Mata and Hazard look dangerous already today.
12 minCech has just received a smattering of boos from the home support as he has his first touch. He left them 10 years ago but them still seem to be holding a grudge against the Chelsea keeper.
15 minCHANCE! The best move and best chance of the match, and it comes for Sparta! The hosts knock the ball about patiently before a string of quick passes results in Zapotocny clipping it in to Lafata, who was stretching to reach the ball but perhaps should have done better. Much better from the hosts, though.
17 minThe hosts are starting to get into this one now. Another nice move sees the ball nodded down to Lafata on the edge of the box. He tries a volley, which is an ambitious effort, but it is blocked before it could trouble Cech.
19 minSparta just look like they have eased themselves into this one after a shaky start, and that could have a lot to do with the fact that this is their first competitive match for over two months.
22 minSparta have failed to score in their last eight games against teams from England - on ominous record for the Czech fans.
24 minThe game is in a bit of a lull at the moment, there is not much to report. Sparta are just knocking the ball about in their half, and are being allowed to do so by Chelsea.
25 minSHOT! Sparta continue to work the ball about and eventually make their way up the field. Kadlec gets the ball just inside the box and lays it off to Matejovsky, who smashes his shot high over the bar.
27 minSHOT! Cech finally has something to do as Krejci gets to the ball first and volleys towards goal. The ball bounces and Cech momentarily looks like he's gone to ground too early, but he reaches up and plucks the ball out of the air with minimum fuss.
29 minUPDATE! Liverpool have gone behind in their match against Zenit, which kicked off an hour before this game. It was Hulk who got it, and it was a fine strike from the Brazilian.
30 minUPDATE! It's two in quick succession for Zenit as they double their lead almost immediately! Samek got the goal this time.
30 minCHANCE! Meanwhile, back in Prague Lafata squanders another great chance. A shot comes off Mata and loops over the defence, straight into the path of Lafata, but the new signing slides in and sends his effort quite embarrassingly wide. Best chance of the game.
32 minMatejovsky slips in Kadlec, but he is forced out wide and eventually eased out for a goalkick. Chelsea started well in the first 10 minutes, but since then it has been all Sparta.
34 minCHANCE! Chelsea against hit the hosts on the counter attack. Marin slides Hazard in down the left, and his ball across to Mata finds the Spaniard in space. His first touch is unusually poor and he tries to slip Torres in, but the striker was stretching for it and couldn't get enough on it to beat the keeper.
37 minChelsea are now enjoying the majority of the ball, but again are lacking attacking intent.
38 minCHANCE! The visitors come forward and Mata slips a pass in to Lampard, who in tirn shifts it on to Torres, but he is off balance and again can't get enough on his strike.
40 minYELLOW CARD! A Chelsea attack breaks down and Cahill dives in on Lafata as Sparta threaten to break clear. He is shown a yellow by the ref, and it is the correct decision.
42 minMarin gifts the ball to the opposition inside his own half and concedes a free kick in his haste to win it back. He had a bright first 10 minutes but has been very sloppy since then.
43 minDodgy moment for Cech as he rushes out to deny Kadlec. He grabs the ball right on the edge of the box but fumbles it and is involved in a tussle with the Sparta man, which he wins by just getting a foot to the ball and clearing it out for a throw in.
44 minSHOT! Lampard goes for goal again from the edge of the box, but his shot it straight at the keeper. The dip in front of the keeper stops him collecting it forst time, but the spillage is not bad enough to give any Chelsea player another chance.
45 minHALF TIME: Sparta Prague 0-0 Chelsea
6.48pmNo added time in Prague and, to be honest, nothing has happened that would warrant anything. It's been a pretty poor game all round so far.
6.50pmThe two best chances have fallen to Lafata, and he really should have scored at least one of them. He is currently the top scorer in the Czech league but today is his first appearance for Sparta, and he hasn't made the best of impressions. The first chance was quite tough but he could have done better, while the second one was a bad miss.
6.52pmFor Chelsea, they began well, but really took their foot off the pedal after about 15 minutes. They looked like a team that was more than willing to settle for a draw in this first leg and try to win the tie at Stamford Bridge.
6.54pmHopefully, Sparta will be keen to find a goal in the second half and will show more attacking intent. They have had their brief moments - notably Lafata's chances - but haven't really hit top gear yet.
6.56pmLet's have a look at some stats from that first then, shall we? Chelsea just edged the possession, seeing 52% of the ball, while the visitors also had the most shots with seven. From these seven shots, six were on target, but they are still yet to make Vaclik really work.
6.58pmSparta, meanwhile, need to be more clinical in front of goal. I've already highlighted Lafata's missed chances, but as a team they have only put one of their five shots in target.
7pmChelsea certainly have the ability to grab a goal in this half, but they will have to do better than they managed in the first half.
45 minChelsea get us back underway in Prague.
47 minSHOT! This may be in contention for the worst shot of the season! Krejci cuts inside and goes for goal on his weaker right foot, but his effort swings wildly out for a throw in.
49 minChelsea have a free kick in a good position for a cross, but Lampard's delivery is poor, skimming across the floor before being cleared away by the first man. We've come to expect better from the England international.
51 minSHOT! That's a better effort from Krejci. He goes for goal on his stronger left foot this time, and his 30 yard effort is swerving in mid-air, but it's straight at Cech so doesn't present too much of a problem for the Chelsea keeper.
53 minSparta come forward with Krejci and Kadlec involved. The latter's pull back causes some problems in the Chelsea box, but the defenders eventually hack it clear.
55 minMarin tries to slip a ball into the box towards Torres, but his pass is easily cleared and Torres hadn't even made the run.
56 minCahill scrapes his studs down the back of Krejci's leg, a dangerous move for a man already on a yellow. Sparta pump the ball into the box from the resulting free kick, but Cech easily gathers.
58 minSHOT! It's another shot for Chelsea but again it is not troubling the keeper at all. This time Torres lays the ball off to Lampard, whose snap shot flies well over the bar.
60 minGood defending there from Sparta as Marin threatened to let fly. Torres agains held the ball up before laying it back to the winger inside the box, but he was quickly shut down and his shot was blocked.
62 minSome of the passing today has been truly awful. Simple five-yard passes have gone to a man wearing a different coloured shirt to the one that it was intended for and, I have to say, Chelsea have been the main culprits.
64 minMatejovsky finds Kadlec in the middle and he skips beyond Ramires, who slips over, but his strike is blocked by Cahill.
66 minWe're coming up to the time that Benitez usually brings on a sub, and this match is screaming out for someone like Oscar to come on and light it up. Having said that, the likes of Mata and Hazard should be able to do that too!
66 minYELLOW CARD! Husbauer is the first home player in the notebook for a foul on Ramires.
67 minCHELSEA SUB: Sure enough, Benitez makes the change, but it is not Oscar who comes on. Instead, it is Yossi Benayoun who replaces Marin, who has been poor today.
69 minCHANCE! A rare highlight of this second half and it comes for Chelsea. Mata clips a ball in to Lampard, who can't generate enough power on his header to trouble Vaclik, who makes a comfortable save.
71 minSHOT! Torres has a shot (I use that term loosely) at goal, but it may rival Krejci's earlier effort for the worst of the season. This one also goes out for a throw. Two in one game, that sort of sums this one up.
74 minFair play to the Sparta crowd, they have kept some sort of noise up throughout this one. They certainly haven't been inspired by what is going on on the pitch.
76 minSPARTA SUB: On comes Cameroonian striker Kweuke, replacing debutant Lafata, who has missed the two best chances of the game so far.
78 minKrejci swings a cross into a decent position, but Cech is out to claim it under no challenge whatsoever.
80 minSHOT! Zapotocny swings a ball into Kweuke, who swings a leg at it but can only scuff his shot harmlessly wide. That would've been a good chance if he got clean contact.
81 minCHELSEA SUB: Here comes Oscar, he is on in place of Juan Mata.
81 minGOAL! Sparta 0-1 Chelsea (Oscar)
82 minI told you we needed Oscar on the field! He finally has a bit of attacking intent about him and he plays a one-two with Hazard before sliding the ball past the keeper with his left foot. Hopefully we're in for a more urgent final 10 minutes now.
83 minSAVE! This is more like it! Torres attacks the Sparta defence and works the ball onto his left before letting fly, but Vaclik sticks a hand up to deny the Spaniard. That's a good save that could keep Sparta in the tie.
84 minSPARTA SUB: Former West Brom man Roman Bednar comes on for his debut in place of Husbauer.
85 minSHOT! Svejdik meets a Sparta corner deep into the Chelsea box, and his looping header has Cech worried for a moment, but it drops safely onto the roof of his net.
88 minTorres skips down the right flank and tries to work his way inside, but he is eventually crowded out.
90 minWe will have three minutes of added time in this one.
90+1 minSparta have possession inside the Chelsea and are desperately trying to find room to shoot, but it just won't sit up for them and Cahill eventually scrambles it clear.
90+3 minFULL TIME: Sparta Prague 0-1 Chelsea
7.49pmThere you have it! The ref brings a dull and dreary match to an end but it will go down as a successful one for Chelsea, who win 1-0.
7.51pmThey must be overwhelming favourites to qualify now with the second leg to come at Stamford Bridge. Sparta would need to come to London and score twice if they are to win in normal time, or match the 0-1 scoreline to forced extra time and, to be honest, I can't see that happening based on tonight's performance.
7.53pmThe hosts did have a couple of chances, and probably should have been ahead at the break, but Lafata was guilty of missing both. Chelsea created painstakingly little going forward too, despite making a bright start to the match. I thought that Sparta were there for the taking for Mata and Hazard et al, but they never really got out of second gear.
7.54pmIt took the late introduction of Oscar to separate the sides. The Brazilian added a little sparkle to a dreadful game, scoring just 40 second after coming onto the pitch.
7.55pmRight, that's all we have time for tonight. Thanks for joining Sports Mole on a good night for Chelsea, who have all but booked their place in the next round of the Europa League. You can keep up to date with Tottenham and Newcastle's Europa League matches on site if you haven't had your fill of live football yet, but from me, it's goodnight!