Moyes off the mark with the Hammers as Arnautovic strike sinks Chelsea
West Ham stunned Chelsea in the Premier League's lunchtime kick-off as manager David Moyes collected his first win with the club.
Marko Arnautovic's well-taken early goal, his first for West Ham, proved enough as Adrian - selected in goal ahead of Joe Hart - made excellent saves before half-time from N'Golo Kante and Davide Zappacosta while Alvaro Morata fired a good chance into the side netting in the second period.
Defeat leaves Chelsea 11 points behind Premier League leaders Manchester City, who face second-placed Manchester United on Sunday, and manager Antonio Conte admitted afterwards "i t's impossible to think you are in the title race" with that deficit.
Tottenham ended their four-match winless league run in style with a 5-1 thumping of Stoke at Wembley.
Spurs took a 21st-minute lead through Ryan Shawcross' own goal, and two goals in as many minutes from forwards Son Heung-min and Harry Kane early in the second half made the game safe.
Kane struck again and Christian Eriksen added a fifth before Shawcross headed a consolation.
Jermain Defoe's brace and Asmir Begovic's late penalty save earned Bournemouth a dramatic 2-2 draw at Crystal Palace.
Defoe finished from a corner to put Bournemouth ahead early on but it was in the five minutes up to half-time that the game came to life.
First Wilfried Zaha won a penalty which Luka Milivojevic converted, then Scott Dann tucked away Yohan Cabaye's corner as Palace thought they had taken an interval lead.
Defoe had other ideas, though, looping a brilliant volley over Julian Speroni to leave the scores level once more.
Another penalty gave Palace the chance to win it in injury time but Christian Benteke, stepping up ahead of Milivojevic, saw a feeble effort saved by Begovic.
Burnley won the battle of the Premier League's surprise packages 1-0 against Watford at a snowy Turf Moor.
The Hornets had Marvin Zeegelaar sent off for a studs-up challenge on Steven Defour and Scott Arfield's neat finish right on half-time was enough to clinch the result for Burnley.
Huddersfield moved level on points with 10th-placed Everton after a 2-0 win over Brighton.
Steve Mounie was the Terriers hero, opening the scoring early on and heading a second shortly before half-time when an awkward bounce embarrassed keeper Mat Ryan.
Wilfried Bony's goal nine minutes from time earned Swansea a much-needed 1-0 win over West Brom.
Jake Livermore deflected a Ki Sung-yueng free-kick onto his own post in an otherwise drab first half while Ben Foster saved well from Jordan Ayew in the second before Bony finally broke the deadlock with a ferocious finish.
Newcastle forward Ayoze Perez's own goal settled an entertaining evening game 3-2 in favour of Leicester.
Joselu put Newcastle in front early on at St James' Park but Riyad Mahrez levelled from long range before half-time.
Deflected strikes from Demarai Gray and the impressive Dwight Gayle made it 2-2 but Leicester won it when Jamie Vardy crossed to Shinji Okazaki and Perez, inexplicably the only United player in position to prevent him getting a shot away, could only poke the ball past his own keeper.