Saturday's Premier League reports
Chelsea 3-1 Arsenal
Chelsea tightened their grip on the Premier League title race and delivered a blow to Arsenal's aspirations with a convincing victory at Stamford Bridge.
Marcos Alonso opened the scoring from close range when he headed in the rebound after Diego Costa's effort hit the crossbar.
The Blues doubled their lead seven minutes after the break when Eden Hazard tucked the ball past Petr Cech after a fantastic individual run which began on the halfway line.
Cesc Fabregas put the game beyond his former club when he lobbed past Cech after a poor clearance.
Olivier Giroud scored a late consolation goal for the visitors, who are now 12 points behind the league leaders.
Crystal Palace 0-4 Sunderland
Sunderland scored four first-half goals to thrash Crystal Palace at Selhurst Park as the Black Cats moved level on points with their Premier League relegation rivals.
Lamine Kone reacted quickest to Wayne Hennessey's spill to steer in Sunderland's opener after 10 minutes.
The visitors then scored three goals in six minutes in a stunning end to the first half as Didier Ndong struck a superb effort from 25 yards before Jermain Defoe punished lax Palace defending with two excellent finishes.
A fan got onto the pitch to confront Damien Delaney as the Palace players were booed off at half-time on a miserable afternoon for Sam Allardyce against his former club.
Sunderland easily controlled the second half to secure their first away Premier League win in six games and join Palace on 19 points.
But David Moyes' side remain bottom of the table following Hull City's 2-0 victory over Liverpool.
Everton 6-3 Bournemouth
Romelu Lukaku helped himself to four goals as Everton extended their unbeaten Premier League run to seven games with a thrilling victory over battling Bournemouth at Goodison Park.
Lukaku curled home an exquisite opener after just 30 seconds to equal the record for the fastest league goal of the season set by Chelsea's Pedro against Manchester United.
Lukaku's trickery set up James McCarthy for Everton's second before the Belgium striker took his tally to 15 goals for the season when Simon Francis' suicidal back pass gifted him the opportunity to apply a lofted finish over Artur Boruc.
Joshua King's second-half brace gave Bournemouth hope, but Lukaku added two more inside the final 10 minutes to put the game to bed, although there was still time for Harry Arter to add a third for the visitors and Ross Barkley to slot in Everton's sixth.
The result was a fitting way for Everton manager Ronald Koeman to celebrate his 100th Premier League game, and takes the seventh-placed Toffees to within two points of Manchester United.
For slumping Bournemouth, meanwhile, defeat takes them to within six points of the relegation zone. Eddie Howe's men - winless in 2017 - are now on a run of one victory in eight and have conceded 34 goals in their last 13 games - shipping at least three goals in nine of those.
Hull City 2-0 Liverpool
Alfred N'Diaye scored on his Hull City debut as Liverpool's terrible start to 2017 continued with a fourth defeat in five league and cup games.
Senegal forward N'Diaye, signed on loan from Villarreal, tapped home unmarked after Simon Mignolet dropped the ball at his feet.
Despite striker Sadio Mane's first start since 2 January, Liverpool failed to force a single save in the first half and were poor throughout.
Jordan Henderson was denied by Eldin Jakupovic but Hull, who have won all four home games under Marco Silva, sealed victory when Oumar Niasse, on loan from Everton, kept his composure after the Reds defence had been carved open.
Southampton 1-3 West Ham
West Ham came from behind to beat Southampton and move into the top half of the Premier League.
The Saints took an early lead when Manolo Gabbiadini blasted in an opener on his debut after a £14m move from Napoli on transfer deadline day.
But Andy Carroll equalised when he finished after a fine pass from Pedro Obiang, who then put the Hammers ahead with a 30-yard low effort.
West Ham grabbed a third as Mark Noble's free-kick deflected in off Saints midfielder Steve Davis.
Watford 2-1 Burnley
M'Baye Niang scored one goal and made another on his Watford home debut as 10-man Burnley's miserable away record continued.
Sean Dyche's side, who have not won on their travels in any competition since last May, lost midfielder Jeff Hendrick to a sixth-minute red card for a two-footed challenge on Jose Holebas.
Niang, signed on loan from AC Milan last month, then crossed for Troy Deeney to head his third goal in four matches.
The winger then guided in Holebas' left-wing cross with a fine header just before half-time.
Ashley Barnes gave Burnley hope by scoring a penalty with 12 minutes left after Sebastian Prodl handled Joey Barton's shot - but they could not equalise.
West Bromwich Albion 1-0 Stoke City
James Morrison's early goal was enough to ensure West Brom beat Stoke at The Hawthorns to consolidate their place in the top 10.
The Baggies started brightly, with Salomon Rondon netting inside four minutes only to be flagged offside.
Morrison latched onto Nacer Chadli's pass and tapped it past Lee Grant after six minutes.
Saido Berahino, who moved from the Baggies to Stoke in January, was booed when he came on in the 58th minute.
The hosts were rarely troubled and are now unbeaten in five Premier League games against the Potters.
Tottenham Hotspur 1-0 Middlesbrough
Tottenham re-established a nine-point gap to Premier League leaders Chelsea with a workmanlike victory over Middlesbrough at White Hart Lane.
Chelsea had moved 12 points clear with their impressive 3-1 win over Arsenal in the lunchtime kick-off, but Harry Kane's second-half penalty ensured Spurs did not cede any ground to their London rivals.
Tottenham now have clear air in second place after defeats for nearest challengers Arsenal and Liverpool, although fifth-placed Manchester City could close back to within a point when they play on Sunday.
Tottenham's seventh successive home win was secured when Kane fired home from 12 yards after Son Heung-min was hauled down in the area by Bernardo Espinosa and referee Mark Clattenburg correctly pointed to the spot.