Hazard scored all three goals as Chelsea saw off Newcastle 3-0 to go top of the table for the first time since September.
The Blues were without John Terry for the first time this season in the league due to a muscular strain. David Luiz switched to centre-back, with Frank Lampard and Oscar coming in. Luuk de Jong started for Newcastle for the first time, while Cheick Tiote was out injured.
Hazard's first goal came on 27 minutes, the Belgian getting on the end of a Branislav Ivanovic pass from the right towards the edge of the area and slotting across Tim Krul.
Soon afterwards, Petr Cech saved from Moussa Sissoko in a one-on-one situation, and Chelsea scored again on the counter-attack. Willian spread the play wide left to Hazard, who ran into the area and executed a classy one-two with Samuel Eto'o before finishing coolly.
Newcastle lost Mathieu Debuchy to injury before the break, and fell further behind when the defender's replacement Mapou Yanga-Mbiwa flattened Eto'o off the ball. Hazard stepped up and completed his treble.
James Milner, Gael Clichy and Stevan Jovetic all started for Manuel Pellegrini's side, with Edin Dzeko dropped to the bench. January signing Joseph Yobo and transfer rebel Wes Hoolahan were included in the Norwich line-up.
The Canaries thought they had gone ahead on 18 minutes. Joe Hart could only parry Leroy Fer's powerful header and the ball dropped to Gary Hooper, who poked it over the line - only to see the flag had gone up.
On 36 minutes, Jesus Navas' corner was glanced on by Martin Demichelis and Alvaro Negredo thumped a header off the face of the crossbar.
The visitors threw everything at Chris Hughton's side in the second half but couldn't find a way through.
At Anfield, Liverpool reignited their title challenged with a sensational 5-1 thrashing of Arsenal, who had begun the day in top spot and were on an eight-game unbeaten run.
Martin Skrtel got a knee to Steven Gerrard's free-kick after just 52 seconds, and the same combination helped the Reds double their lead when Skrtel flicked in a header from Gerrard's corner on 10 minutes.
Luis Suarez then volleyed against the post from another Gerrard corner, but a third goal would arrive on 16 minutes when Suarez crossed from the right for Raheem Sterling to score.
Four minutes later, Daniel Sturridge grabbed the fourth from a superb Philippe Coutinho throughball.
Kolo Toure's pass over the top was converted by Sterling at the second time of asking for a fifth goal on 52 minutes, and Arsenal - who had Jack Wilshere back in their side - were only able to muster a penalty goal consolation from Mikel Arteta (69).
Scott Dann, Tom Ince and Joe Ledley all made their Eagles debuts and the latter two were able to mark the occasions with goals.
Youssouf Mulumbu cleared Dann's header off the line early on, but Ince gave the Eagles the lead on the quarter-hour mark when he lifted the ball over Ben Foster after good work from Yannick Bolasie.
On 27 minutes, Tony Pulis' men doubled their lead as a corner whipped in by Ince was met by an unmarked Ledley
Immediately after the break, Thievy pulled a goal back for Albion with his first touch since coming on as part of a double switch by Pepe Mel. Victor Anichebe, on the left wing, played a lovely ball back to the substitute who fired in an unstoppable finish.
But Marouane Chamakh restored Palace's two-goal advantage from the penalty spot, after referee Chris Foy adjudged that Foster had brought down the Moroccan in the area.
England boss Roy Hodgson was watching at the Stadium of Light, with the Black Cats' Adam Johnson having netted seven in seven prior to this game - but he was unable to impress on this occasion.
In the fourth minute, Wes Brown was shown a red card - Sunderland's fifth under Gus Poyet - for hacking down Shane Long when the Hull striker was through on goal. Brown's error came from a dreadful pass from Phil Bardsley which put his team-mate in trouble.
Vito Mannone saved Tom Huddlestone's resulting free-kick and Fabio Borini was sacrificed by Poyet in order to bring on Santiago Vergini, but on 16 minutes, Hull went in front.
Huddlestone's corner was headed away from Mannone by Jozy Altidore but Jake Livermore guided the ball back into the danger zone and Long was lurking to head home from close-range.
Jelavic scored a second with a 62nd-minute header after the ball had looped up off the heels of Vergini from Maynor Figueroa's drive. The Black Cats are 17th, one point above West Brom.
Carlton Cole replaced the banned Andy Carroll for the Hammers, while Gabby Agbonlahor returned to captain Villa.
In the first half lacking any real quality, Stewart Downing missed his kick right in front of goal before Matt Jarvis drove his sliding right-footer wide of Brad Guzan's near post.
Marco Borriello replaced Cole at the break, and within three minutes, West Ham had scored twice through Nolan.
First, Stewart Downing turned Ryan Bertrand inside out before his low cross was superbly turned home thanks to some brilliant improvisation by Nolan, scoring with a backheel.
Then Nolan nipped in to steal the ball off Fabian Delph before slotting his right-footer beyond Guzan into the far corner for his fourth goal in two games.
After a needless sixth-minute handball from Charlie Adam, Rickie Lambert opened the scoring as his free-kick flew across goal and over Asmir Begovic into the far corner.
Peter Odemwingie equalised on 38 minutes. A wonderful Adam pass carved Saints open and put the Nigerian through to slide the ball past the onrushing Artur Boruc.
Three minutes later, Steven Davis cut inside and whipped an a excellent cross into the middle, which bounced, evaded everyone, and was then carried in by the wind.
However, Stoke levelled before the break when Peter Crouch took advantage of sloppy marking and headed in Adam's corner.
In Saturday evening's late game, Wayne Routledge claimed a goal and an assist as Garry Monk's Swansea won 3-0 at home to Cardiff in the south Wales derby.
Routledge, who had a loan spell with the Bluebirds five years ago, did the damage against his former club on Saturday evening as Monk began his spell as Swans manager with a much-needed three points.
The result at the Liberty Stadium moved the hosts up to 10th in the Premier League table, four points clear of the drop zone where their beaten opponents remain. Cardiff are 19th, three points from safety.
After a dreary first half, Monk introduced Pablo Hernandez to the action for the second period and within two minutes, the Spaniard had sent Routledge racing away down the left to score past David Marshall.
Craig Bellamy hit the crossbar for the visitors soon afterwards, but they were undone once more as Routledge crossed from the left in the 79th minute for Nathan Dyer to stoop low and direct a header into the corner.
A third goal followed five minutes from time for record signing Wilfried Bony, heading home from close range after Pablo's free-kick.