Chelsea John Terry Gary Cahill
Chelsea skipper John Terry celebrates with Gary Cahill after scoring the winner against Southampton, December 1. Reuters

Staring down the barrel at Chelsea's first home defeat under Jose Mourinho at the 66th time of asking, the home side responded, like they always do, with an assured second half performance to pull off an impressive 3-1 victory over Southampton, who have now suffered back-to-back defeats in London.

With Arsenal winning on Saturday, the onus was on the chasing pack to keep within touching distance on a Sunday which saw most of the big boys strut their stuff, or at least attempt to.

Tottenham and Manchester United failed to a degree, only managing a draw amongst themselves at White Hart Lane, while Liverpool jumped into a bunker and could not find a way out as Hull had their number at the KC Stadium.

Manchester City responded well with a 3-0 victory over Swansea, and so did Chelsea, scoring three goals in the second 45, to cancel out Jay Rodriguez's opener, scored after just 13 seconds.

Mourinho made a crucial change at halftime, bringing on Demba Ba for Michael Essien as Chelsea went to a 4-4-2, which eventually proved to be a game changer.

"The [Southampton] goal was like a knife in my back, we weren't ready for that and by surprise we were losing 1-0," Mourinho said. "I knew everyone would be speaking about a very good second half but in the first half I thought we played very well.

"We played with balance, no silly decisions, no mistakes, not going from 1-0 to 2-0. Even my change, when I had to change Oscar, it looked defensive, because we replaced [the injured] Oscar with [Frank] Lampard, but it was to prepare for the second half.

"I had to take Essien off and play with two strikers as he had a yellow card in a crucial area of the pitch. We went to 4-4-2 and we gave Southampton a different game, a game they didn't expect and it was difficult for them to cope with the situation."

Gary Cahill equalised with an opportunistic strike in the 55th minute, before skipper and talisman John Terry headed in wonderfully well on 62 minutes to mark his 400th Premier League appearance.

Demba Ba, who had a big hand in the home side's opening goal, made the game safe late on as Chelsea pulled to within four points of Arsenal.

"Step by step they are understanding my ideas and my mentality, feeling the responsibility, feeling that Chelsea cannot be completely out of the title race in December," Mourinho added. "They must feel the responsibility to play for Chelsea and that was a sign of maturity. They were losing after 10 seconds but kept calm.

"My team is one with a profile where I can't establish targets. I can't say I want to win five consecutive matches or be top of the league. I just want to work with them, feed the young players, feed the team and if we do that we are there.

"If you are 10-12 points behind you are building but you are not fighting for the title, if you are three, four or five behind you are building but you are fighting for the title. One of the things these boys need to learn is coping with the responsibility of being there, we cannot be 15 points behind by December, we have to be there."

Chelsea next face second from bottom Sunderland at the Stadium of Light on Wednesday.