The Black Cats equalised through John O'Shea, but Hazard restored Chelsea's lead with a curling shot.
A Phil Bardsley own goal made it 4-2, and although the same player pulled one back for the hosts, Chelsea held on.
Read how it all unfolded below.
6.43pmHello there! Thanks for joining us tonight for Sunderland vs. Chelsea in the Premier League. It's a busy night of action, so stay in, forget about the soaps on TV, and get ready for some great football.
6.46pmChelsea travel to the Stadium of Light knowing that a win could move them to within one point of league leaders Arsenal. But, Sunderland are also in need of the points after Crystal Palace's win sent them to the bottom.
6.50pmIt's a special night for Gus Poyet, who comes up against his former club for the first time as a manager. However, more on that later. Let's have a look at the teams.
6.54pmSUBS: Schwarzer, Cole, Essien, Mikel, Schurrle, De Bruyne, Ba
6.56pmThe Black Cats make two changes from the team that drew 0-0 with Aston Villa. Jozy Altidore and Jack Colback replace Steven Fletcher and Seb Larsson.
6.59pmChelsea also make two switches, bringing in Frank Lampard and Willian for Michael Essien and Oscar.
7pmSo, Poyet goes with two strikers - Altidore and Borini - as he seeks to continue his decent start as Sunderland boss. As I mentioned earlier, this is the first time he has faced Chelsea as a head coach.
7.03pmSpeaking before tonight's match, he claimed that it would be a "special day" for him, and told ChronicleLive that there would be "friendship and talking" before the match, but certainly none during it.
7.06pmThere's no doubt that this is a tough test for Sunderland tonight, but they surprised many people by beating Manchester City, and a positive result is not beyond them.
7.09pmAfter Palace's win over West Ham, the home side will be desperate to haul themselves off the bottom. However, the problem all season has been scoring goals.
7.10pmPoyet's men have scored just eight league goals, at an average of 0.62 per game. They have also had just 30 shots, which is fewer than any other side.
7.13pmAgainst Villa they had only one effort on target, and despite the upturn in performances since Poyet's arrival, Sunderland have scored only three goals in his first six games.
7.15pmCould that change tonight? Well, the stats certainly only point one way - a Chelsea win.
7.17pmHere's one I found earlier: Chelsea have won 16 of their last 17 league games against Sunderland. The last time the Black Cats took anything from their opponents at home was in December 2001 when they drew 0-0.
7.18pmThe home players begin their pre-match warm-up.
7.22pmSo, what about Chelsea? This season has been a mixture of good and bad for Jose Mourinho. Yes, they are second in the league, but they have struggled to produce their best away from home. They have also been beaten twice in their Champions League group.
7.24pmMourinho was clear after Sunday's win against Southampton that his team are still a work in progress, saying that things were going "step by step".
7.25pmHowever, given their run of form against Sunderland, it would be fair to say that Mourinho expects his players to take another step forward tonight. Although, he warned his players not to take the Black Cats lightly.
7.28pm"I think they are better than the points they have. The quality of their players is not comparable with some teams in that part of the table, but I think they are in a moment where one point doesn't make a big difference," he told reporters.
7.31pmFrank Lampard has also had his say on the season so far. "We're striving to put together a run of wins. We need to carry on from our last two league games," he said before the match.
7.34pmA win tonight could be huge for Chelsea. Depending on what happens at the Emirates between Arsenal and Hull, the Blues could be just one point behind the leaders come 10 O'clock.
7.37pmIt's almost time for kickoff at the Stadium of Light. What are your predictions? I'll give you mine in a few minutes.
7.42pmPrediction: As promised, here's my say on the result. Despite Sunderland's recent record against Chelsea and lack of goals, I think this could be a close match. However, the away side's quality will edge it. 2-1 to Chelsea.
7.44pmThe players are out and we're just moments away from kickoff.
0 minKICKOFF: The home side get us underway. Here we go.
1 minNo goalmouth action as yet, although Emanuele Giaccherini just had a long-range shot blocked.
2 minOoh! Good play from Borini sees him jink past a defender and fire a shot across the face of goal. It went well wide, but a decent start by the home side.
4 minDangerous moments in the Sunderland box as Hazard picks out Mata, who fires a ball into the box. However, O'Shea and Brown just manage to clear.
5 minIt's been a bit of a scrappy start from the visitors. They look almost nervous in possession, and shaky at the back.
7 minOVER THE BAR! This is better from Chelsea. Willian works hard to win the ball, before finding Hazard. The Belgian takes a touch and decides to launch a long-range shot. However, it has too much power and goes over.
9 minChelsea are starting to look more confident on the ball, particularly in midfield.
10 minWIDE! Again it's a shot from distance for the Blues, as this time Lampard strikes low and hard past the post.
12 minSunderland have a free kick outside the box after Azpilicueta barged into Altidore. This could be dangerous.
17 minIt's 1-1 now, and what a brilliant response from Chelsea. The corner makes its way to Hazard, who clips in a lovely cross which finds Lampard's head after a trademark run into the box.
20 minMourinho's men are on top now. Since Sunderland's goal it's been all Chelsea and the Black Cats are finding it hard to keep hold of the ball.
21 minNow then, was that a penalty? Ramires runs with the ball from the edge of the box and goes over following a challenge by Brown. However, Phil Dowd is having none of it. On closer inspection it looks like a correct decision.
24 minThat's better from Sunderland. Colback gets a loose Torres pass and feeds Giaccherini, who wins his side a free kick.
26 minCraig Gardner's ball is dealt with and the match has now settled down after that frantic start.
27 minWIDE! You'd have to say that Chelsea look the more likely to score at the moment. They have the edge over their opponents in the final third, and Hazard is up for this one. Nevertheless, Lampard's shot rolls wide and it's a goal kick.
28 minGood defending by Cahill as he slides in to cut out a Giaccherini cross. Despite conceding, Poyet must be pleased with the start his team have made.
30 minSAVE! Positive play from Sunderland sees Ramires's clearance go straight to Dossena and the left-back lets rip with a volley, but Cech tips over for a corner.
33 minCHANCE! Torres should do better here. Mata's cross is cleared to the striker, but he snatches at his effort it goes well over.
35 minThis is a brilliant goal. Pure class. Torres flicks a header to Hazard, who is out wide. The Belgian cuts inside and bends a lovely shot past Mannone in the Sunderland goal. No chance for the goalkeeper there.
38 minYELLOW CARD Dossena picks up a booking for a challenge on Mata. The Chelsea man is down and is in pain, and yes, on the replay its looks like a sore one.
41 minMata is fine to continue, and is involved in a passing move which ends when his cross drifts out of play.
42 minOh Fernando! Lampard plays a delicious ball over the top of the Sunderland defence, but Torres is unable to get it under control and is crowded out by the defence.
45 minSAVE! Hazard is on fire tonight. This time he twists and turns on the corner of the box, before smashing the ball at goal. It's a decent save, but Sunderland need to stop Hazard.
8.37pmRight, Chelsea have had 57% of possession, and eight shots compared to Sunderland's six. Only one of the home side's was on target, while Chelsea had three.
8.38pmA little bit of housekeeping before we continue the half-time analysis. Bardsley got a yellow card just before the break after bringing down Hazard.
8.40pmThat bring us nicely onto Hazard, who has been a joy to watch. His cross for Lampard's equaliser was perfectly delivered, and his finish for the second was pure class. Sunderland need to find a way to restrict his influence in the second half.
8.42pmHowever, the Black Cats more than played their part. In some respects they might feel aggrieved to be 2-1 down, especially after Altidore had given them a 13th minute lead with a smart turn and finish.
8.45pmUPDATE Elsewhere in the Premier League tonight, Arsenal are beating Hull City 1-0 thanks to a Nicklas Bendtner goal, which means that as it stands, Chelsea are second with 30 points, four behind the Gunners.
46 minKICKOFF The second half is underway. Can Chelsea extend their lead and keep up the pressure on Arsenal? Or, will Sunderland fight back and maintain Gus Poyet's 100% home record?
47 minThe link-up play between Hazard and Mata is a key reason why Chelsea are 2-1 ahead, and the pair start the second half where they left off in the first, using the ball to twist and turn their opponents.
49 minWhat a start to the half for Sunderland! The roof is almost lifted off the stadium, but Chelsea should have done better. Borini fires in a low corner, Brown misses it, but O'Shea smartly turns it home. It was sloppy defending by the Blues and they should have cleared the ball.
50 minJust as in the first half, Chelsea respond by racing up the pitch and Torres flashes a cross across the face of goal. If only one of his teammates had gambled on that, it could have been 3-2.
52 minYELLOW CARD Jack Colback is booked for trying to bring down Willian during a Chelsea counter-attack.
54 minOh Colback! The Sunderland midfielder runs the risk of a red card by pulling back Ramires. Dowd thinks about it, but decides to keep his cards in his pocket.
56 minWHAT A MISS! Torres, hang your head in shame. What a shocking miss this is by the Spaniard. Hazard does brilliantly again, skipping past challenges as if they don't exist, before smashing at shot at Mannone. The ball rebounds to Torres, but he blazes his shot over the bar from no more than six yards.
58 minSUNDERLAND SUB: Poyet decides that's the end of the night for Colback and on comes. Sebastian Larsson
61 minWell, what can you say about Hazard tonight? He has been simply unstoppable on the ball. He runs down the left, plays a one-two with Lampard and charges into the box, dancing around Sunderland defenders before thumping the ball past Mannone. Superb.
64 minYELLOW CARD Hazard is booked for removing his shirt during his celebration.
CHELSEA SUB: Ex-Newcastle man Demba Ba comes on to replace Torres, who was disappointing.
65 minSUNDERLAND SUB: Poyet responds to that change by making his second of the night. On comes Adam Johnson for Giaccherini.
67 minWhere do Sunderland go from here? They are by no means out of this game, but as long as Hazard is on the pitch, it's hard to predict anything but a Chelsea win.
69 minThe home side have settled down since Chelsea's third goal, but they haven't created anything since falling behind for the second time of the night.
71 minGood defending by O'Shea sees the ball go out for a corner after Hazard and Mata had again created space on the right.
72 minWIDE! Willian should do much better here. A corner is cleared, but Johnson then gives it straight back to Chelsea, who work the ball to Willian. He runs into the box, but loses his composure and smacks a shot wide of the post.
73 minCHANCE! Demba Ba is in a great position on the edge of the box, but curls his shot wide. However, the hands go up on the Chelsea bench and there are big appeals for a penalty. There appears to be a definite tug on the striker's shirt, but once again Dowd isn't interested.
75 minNow Sunderland claim for a penalty after Borini tumbles under a challenge from Azpilicueta. Dowd shakes his head again and Chelsea regain possession.
79 minCLOSE! Almost 4-2 to Chelsea! Ramires bursts forward, showing skill, strength and determination to force his way past a defender. The angle isn't favourable, but he takes a shot anyway and places the ball just wide of the post.
81 minSUNDERLAND SUB Huge cheers go around the Stadium of Light as Steven Fletcher enters the action for Craig Gardner.
83 minGame over. Chelsea wrap up the win with a fortuitous goal. Ramires pushes forward in midfield, before sliding the ball down the right for Ba. The striker crosses to the penalty spot, and Bardsley slides in to divert the ball into his own net.
85 minWhat was I saying about it being game over? Ha Ha! Sunderland are right back in this contest, and what a few minutes for Bardsley! Chelsea fail to clear a Larsson corner, and there's Bardsley to poke home. And now the home fans roar.
87 minThis is end-to-end now, and the home fans are loving it. Mourinho, on the other hand, looks anxious. Can his team hold on?
88 minYELLOW CARD AND CHELSEA SUB Willian is booked and then replaced by Andre Schurrle as Mourinho looks to waste some time.
91 minWhat a great second half we've had tonight. There is so much space in midfield and both teams are pushing forward.
93 minWhat pressure from Sunderland. Chelsea are camped in their box now. However, Borini fires wide and the Blues can breathe again.
94 minCHANCE! Oh! Adam Johnson! The former Manchester City winger has to do better, no question. Ki Sung-Yueng goes on a mazy run on the edge of the box, before passing to Johnson. However, he opts to cut in on his left foot instead of hitting it with his right and the move breaks down.
9.42pmMy word. What a night of football at the Stadium of Light. The match had it all. Great goals, great individual performances, a shocking miss, and an own goal.
9.44pmDespite the defeat, credit has to go to Gus Poyet and his players. They kept coming back at Chelsea, even when the match appeared to be over after Bardsley's own goal. However, they were no match for the quality of Hazard. At times he was on another planet.
9.46pmChelsea stay second, four points behind Arsenal after the Gunners beat Hull City 2-0. Sunderland, meanwhile, remain bottom with eight points.
9.49pmThat's all from me folks. Thanks for joining us here at Sports Mole for tonight's action. Make sure you stay on the website for all of the latest reaction.