John Terry came to his sides rescue with a goal on his 400th Premier league appearance to save Chelsea's blushes and move them to second in the table following Liverpool's defeat to Hull earlier in the day. Terry's goal will have come as a huge relief to Michael Essien who gifted Southampton a 1st minute lead, as his sloppy back pass presented Jay Rodriguez with an early Christmas present and he duly rolled the ball past the bewildered Peter Cech. The early goal gave Saints something to defend and it was easy to see why they had the best defensive record in the league coming into this game, with Dejan Lovren and Jose Fonte solid in central defence, shielded superbly by Victor Wanyama and Morgan Schneiderlin. After 19 minutes Oscar had Chelsea's first shot on target as he weaved into space on the edge of the box before powering a shot that Artur Boruc could only paw away. Chelsea's best chance of the half came just before half time when Hazard evaded Fonte down the left and fed Mata, who found Torres with a cross, but the Spainard's downward header was kept out brilliantly by Artur Boruc. Demba Ba replaced the disappointing Essien at half time and it proved to be a masterstroke by Mourinho. Although Southampton started the 2nd half brightly, Chelsea found themselves level after 55 minutes through Gary Cahill. Mata's corner was headed down by Torres and Ba turned the ball against the post, with Cahill on hand to head home the rebound. Artur Boruc was injured in the build up to the goal and was replaced by young understudy, Paolo Gazzaniga. The goal gave Chelsea new belief, and seven minutes later, it was another set piece that put them ahead. Mata's corner broke to Lampard who returned the ball to the little Spaniard. His cross then found the head of Terry, who firmly planted his header past the despairing Gazzaniga. Chelsea were galvanised, while Saints looked to run out of steam, having pressed so well in the first half. Chelsea put the game beyond doubt in the 90th minute, when Ramires rode a couple of tackles before delivering to supersub Ba, who slid home left footed. Chelsea moved up to 2nd with the win, and Mourinho's fantastic home record stayed in tact. Pochettino will be thinking of what might have been after their excellent first half display. Saints move on to face Aston Villa at home next and will hope to return to winning ways, while Chelsea are away at Sunderland.