Chelsea responded from conceding a Charlie Adam goal from inside his own half and losing Diego Costa to a hamstring injury to beat Stoke 2-1 and move seven points clear in the Premier League title race.
Stoke midfielder Adam's 65-yard strike soared over Thibaut Courtois to cancel out Eden Hazard's penalty opener before Loic Remy struck the winner after substitute Costa had come and gone.
The 20-goal striker, not considered fit enough to start, was introduced at half-time but lasted just 11 minutes as his fragile hamstrings forced his withdrawal in an injury which could have repercussions for the title race.
Jose Mourinho's Chelsea lead second-placed Arsenal by seven points, with Manchester United a further point behind in third, while holders Manchester City are nine points behind in fourth ahead of Monday's trip to Crystal Palace.
Arsenal kept up the pressure at the top of the table as Liverpool were blown away 4-1 at the Emirates Stadium, where Reds contract rebel Raheem Sterling failed to make an impact.
Barclays Prem
W Brom 1 - 4 QPR
Chelsea 2 - 1 Stoke
Swansea 3 - 1 Hull City
Man Utd 3 - 1 A Villa
Everton 1 - 0 So'ton
Leicester 2 - 1 West Ham
Arsenal 4 - 1 Liverpool
All the pre-match headlines had been over Sterling's declaration he was "not a money-grabbing 20-year-old" despite rejecting Liverpool's offer of a new deal, said to be worth some £100,000-a-week.
However, the England forward blew his big chance to show why he is worth a pay rise, unable to convert a golden chance in the first half before Arsenal struck three goals in the space of just eight minutes to settle matters.
Hector Bellerin rolled in a superb curling effort, with Mesut Ozil's free-kick and a blistering 20-yard strike from Alexis Sanchez effectively settling the contest before a fine late effort from Olivier Giroud sealed Arsenal's seventh straight league victory.
Liverpool netted a consolation penalty through captain Jordan Henderson - awarded for a foul on Sterling - but then saw Emre Can sent off for two yellow cards as a second successive defeat dealt a massive blow to their hopes of a top-four finish.
Manchester United's 3-1 home victory over Aston Villa moved them into third and just a point behind Arsenal.
Ander Herrera opened the scoring just before half-time and Wayne Rooney doubled their lead with a superbly-taken goal with just 11 minutes remaining.
Villa hit back immediately through Christian Benteke but could not force an equaliser and conceded an injury-time third as Herrera struck again.
The battle at the bottom of the table took further twists as both Leicester and QPR picked up wins.
Bottom club Leicester are now four points from safety after beating West Ham 2-1 at the King Power Stadium.
Barclays Prem
1 Chelsea 70
2 Arsenal 63
3 Man Utd 62
4 Man City 61
5 Liverpool 54
6 So'ton 53
7 Tottenham 53
8 Swansea 46
9 West Ham 42
10 Stoke 42
11 Everton 37
12 C Palace 36
13 Newcastle 35
14 W Brom 33
15 Hull City 28
16 A Villa 28
17 S'land 26
18 QPR 25
19 Burnley 25
20 Leicester 22
Esteban Cambiasso scored an impressive opener but David Nugent missed a penalty as the Foxes failed to double their lead.
Cheikhou Kouyate levelled for Sam Allardyce's visitors before Andy King scored the later winner to keep Leicester in the hunt for Survival.
QPR's victory was emphatic as they travelled to West Brom and ran out 4-1 winners.
Eduardo Vargas and Charlie Austin had Chris Ramsey's side two goals ahead before Bobby Zamora netted a well-taken third before the interval.
Victor Anichebe pulled one back for the hosts who then had Youssouf Mulumbu sent off as their hopes of a spectacular comeback were ended - especially when Joey Barton scored a fourth in the final minute.
Hull remain in the relegation battle after losing 3-1 at Swansea - with David Meyler sent off to add insult to injury.
Ki Sung-yueng opened the scoring for the Swans, with Bafetimbi Gomis doubling their advantage with a fantastic volley.
Paul McShane halved the deficit but Meyler was sent off moments later before Gomis grabbed his second of the game to seal the points for Garry Monk's men.
Everton were missing Romelu Lukaku but moved up to 11th with a 1-0 victory over a Southampton side chasing European football.
Phil Jagielka's close-range finish proved to be the difference as Ronald Koeman's Saints failed to take the opportunity to move above Liverpool after their early defeat at Arsenal.