Manchester City's hopes of retaining their Premier League title were in tatters as a shock 3-1 defeat at Southampton left manager Roberto Mancini to virtually concede the championship.
Mancini's side needed a victory at St Mary's to keep the pressure on leaders Manchester United, but instead they slumped to their third league defeat of the season.
Jason Puncheon and Steven Davis put Saints 2-0 ahead by the 22nd minute and, although Edin Dzeko got one back before the break, a Gareth Barry own goal early in the second half sealed City's fate.
Mancini's second-placed team have now gone three league games without a win and they remain nine points behind United, who host Everton on Sunday.
"I think we now have a 10 percent chance of winning the title. I don't think United will drop 12 points," said Mancini.
"It was a really poor performance. Southampton were better than us. We conceded two goals which I didn't think a team like us could concede."
While City slumped, Chelsea got back on track.
Manager Rafael Benitez admitted this week that he hasn't spoken to Blues owner Roman Abramovich for three weeks, sparking suggestions the Spaniard could be in danger of losing his job after Chelsea's recent poor run.
But the third placed Blues were too strong for struggling Wigan at Stamford Bridge as a 4-1 win saw them cruise to their first win in five matches in all competitions.
Ramires fired home in the 23rd minute and Eden Hazard doubled Chelsea's lead in the 56th minute.
Wigan replied through Shaun Maloney two minutes later, but in-form England midfielder Frank Lampard and Marko Marin notched late goals to seal the hosts' victory.
"There is a lot of talk and speculation. Nobody is talking to the owner. It is just speculation," Benitez said.
"It is my job to try and win every game. When you have experience of winning things, you know sometimes it can be difficult."
There was less good news for England star Jack Wilshere, who suffered a worrying thigh injury in 10-man Arsenal's 1-0 victory at Sunderland.
Arsene Wenger's team went ahead in the 35th minute when Theo Walcott set up Santi Cazorla and the Spanish midfielder fired home.
Wilshere hobbled off following a strong challenge from Alfred N'Diaye and Arsenal were reduced to 10 men when right-back Carl Jenkinson was dismissed for a second booking after fouling Stephane Sessegnon in the 62nd minute.
Wenger was furious with Sunderland's physical approach, but despite those setbacks Arsenal held on for their third win in four league matches and climbed above Everton into fifth place.
Gareth Bale maintained his sublime form with a brilliant brace to inspire Tottenham's 2-1 victory over Newcastle at White Hart Lane.
Bale added to the growing belief that he is currently the best player in the Premier League with a superb free-kick to open the scoring early in the first half.
The Wales winger then bagged the late winner after Yoan Gouffran had equalised with his first Premier League goal for Newcastle.
Bale now has nine goals in his last 12 league appearances and his heroics extended fourth placed Tottenham's unbeaten run to 10 league games.
"Most teams have to hang on to their best players, Barcelona losing Messi would be a disaster, Real Madrid losing Ronaldo would be a disaster so this is exactly the same," Spurs boss Andre Villas-Boas said when asked about the chances of Bale being tempted to join a bigger club.
"There isn't a release clause, it's very difficult to negotiate with Tottenham as you know and we are not willing to let our best assets go."
Reading's hopes of avoiding relegation suffered a setback with a 2-1 defeat at Stoke.
Brian McDermott's team, two points above third bottom Aston Villa, fell behind when German defender Robert Huth headed in from Glenn Whelan's 67th minute corner.
Cameron Jerome got the hosts' second in the 81st minute and Adrian Mariappa's 83rd minute reply wasn't enough to spark a Reading revival.
Michu scored twice to leave QPR rooted to the bottom of the table after a 4-1 defeat at Swansea.
Angel Rangel and Pablo Hernandez were also on the scoresheet for Swansea, while Bobby Zamora got one back for Harry Redknapp's side, who are six points from safety.
Elsewhere, Norwich shared a dour 0-0 draw with Fulham at Carrow Road.