Chelsea 3-1 Southampton
Chelsea recovered from conceding a goal inside 15 seconds to claim the win that takes them up to second in the table.
And it was the central defensive duo Gary Cahill and John Terry who turned the game on its head with two goals in seven minutes at the start of the second half.
Demba Ba added some late gloss by knocking in his first league goal of the campaign.
It was no more than Jose Mourinho's men deserved after a dominant second half, when they changed formation and cranked up the gears after a spluttering first 45 minutes.
Southampton looked increasingly overwhelmed by the energy and tempo they encountered after the break and their own attacks were sporadic.
Not that the first minute hinted at how the afternoon would pan out. The Blues have been gifted plenty of cheap goals in recent weeks but it was their turn to be generous – and after only 13 seconds.
Michael Essien, given his first league start of the season, lobbed a pass back towards Petr Cech, but the ball ended up in no-man's land. It was just perfect for Jay Rodriguez, though, who seized the stray pass to tuck home.
Offering as buoyant a side as Southampton a leg up was not a good idea, given that the Premier League's surprise package have been discomforting many of the bigger clubs this season.
But it did ensure there would be no sleepwalking from the Blues, who had to step it up immediately and while Southampton have built a reputation as a team that presses high up the pitch, it was Chelsea doing just that in response to the early setback.
Oscar sent a dipping shot at Artur Boruc that had the Saints keeper looking none too clever in palming the ball out in front of him.
The hard working Fernando Torres later whipped in a great cross from the byline that Oscar could not quite guide past Boruc with his head.
Then, Eden Hazard skipped in from the left flank to find Juan Mata and the Spaniard's cross was met by a stooping header from Torres that the Saints stopper did well to keep out.
Essien looked off the pace in the first half, even picking up a booking for a dive. So it was no real surprise that the midfielder departed at the interval, with Ba introduced to create a more attacking formation.
The boldness of the set-up bore fruit 10 minutes after the restart, when Cahill was on hand to nod home after a Branislav Ivanovic header had been flicked onto a post by Ba, exposing the wrong-footed Boruc.
Frank Lampard, on for the injured Oscar just before the break, had sown the seeds of doubt seconds before by rifling a free-kick that was tipped behind for a corner.
It was now a different game, especially as Boruc had to go off injured – Paulo Gazzaniga taking over between the sticks for the suddenly harassed Saints.
Not long after, Mata crossed from the left and it was Terry's turn to flash a looping header into the net – a fitting way to mark his 400 Premier League appearance.
Ba came within a whisker of making it 3-1 when he latched on to Cesar Azpilicueta's long ball, held of a defender and sent a low shot just wide.
No matter. In the final minute, Ramires showed that he has a super-human engine on him, dribbling out wide and back inside before sending in a near-post cross that Ba stabbed home.
Line up: Cech; Ivanovic, Cahill, Terry, Azpilicueta; Ramires, Essien (Ba h/t); Mata, Oscar (Lampard 42), Hazard; Torres (Mikel 84). Subs not used: Schwarzer, Cole, Schurrle, Willian