LONDON - Both Chelsea and Manchester City have capitalised on Liverpool's shock defeat by Hull to leapfrog the Merseysiders and close the gap on Premier League leaders Arsenal.
Chelsea recovered from conceding a goal inside the first minute at Stamford Bridge, when Jay Rodriguez pounced on a poor backpass from Michael Essien, to beat high-flyers Southampton 3-1.
Second-half goals from central defenders Gary Cahill and John Terry, on his 400th league appearance, put Chelsea in front before substitute Demba Ba sealed victory with a 90th minute effort.
The win took Chelsea, now in second place, to within four points of Arsenal.
"What can you do when they score after 13 seconds?" said Chelsea manager Jose Mourinho.
"We kept calm and the second-half performance was really good. We showed heart and a bit of quality.
"In this crazy league this result is important as once again title contenders have dropped points."
Meanwhile City, who went third, were six points adrift of Arsenal after another impressive home display saw Swansea beaten 3-0.
Samir Nasri scored twice after Alvaro Negredo broke the deadlock in just the eighth minute at Eastlands.
"I'm very pleased because we won against a very difficult team, especially when they had possession," said City manager Manuel Pellegrini, who again fielded Costel Pantilimon in preference to England goalkeeper Joe Hart.
Earlier, Hull beat Liverpool for the first time in their history with a 3-1 win at the KC Stadium.
Liverpool started the match in second place but this result dropped them to third, even before Chelsea had kicked-off and City's win meant they finished the day in fourth place.