And that's it! Chelsea thoroughly deserve the three points. Mourinho's men win 3-0.
We will have 4 minutes of time added on.
Chelsea playing a bit of keep ball now. Southampton will just want the final whistle.
Yellow for Clyne for a late one on Azpilicueta.
Hazard off Essien on.
Really impressive performance from Chelsea. They've had too much for Southampton in the second half.
GOAL! Flag stayed down and Oscar continued his run. Slight deflection on his shot past Davis. 3-0.
Southampton looking like they are missing a little bit of self belief at the moment.
Chelsea all over Southampton. Chambers with a rare mistake.
Davis off Ward-Prowse on.
Chelsea win another corner and are in firm control of this one now.
Great strike but fantastic approach play by Oscar. He's been electric.
GOAL! Awesome strike from Willian. Oscar, the other sub, with the assist. Davis no chance.
Oscar does well down the left but his cross is a poor one.
Southampton corner from the left but Chelsea, as they have all afternoon, clear well.
Clyne pushing forward well down the left. Chelsea holding a decent shape at the moment though.
In fact, Lambert connected with the ball but he didn't get enough on it.
CHANCE! Great ball by Clyne down the left and Lambert is inches away. Unlucky.
Chambers hooks the ball away but Southampton struggling to control Oscar and Hazard at the moment.
Lovren booked. Chelsea gathering momentum. Hazard fouled by the corner flag.
Willian nearly has a chance at goal but Southampton get enough bodies back eventually.
Cork off Lambert on.
GOAL! Torres nods in from close range after Oscar's cross is deflected over Davis and onto the post.
Exellent defending by Chambers who heads the cross behind. He's been superb this afternoon.
Southampton corner from the left. Cech clears really well.
Hazard getting on the ball more and more now. It was his ball to Oscar in the first instance.
Yellow for Oscar. He was clean through and went down. Good decision.
Double Chelsea substitution: Willian and Oscar on, Mata and Schurrle off.
Cork receives a yellow for an earlier foul. Chelsea win a corner.
Azpilicueta gets a slice on good luck as his clearance rebounds off Clyne and behind for a goal kick.
Hazard is fouled by Chambers. Looked harsh.
Chambers with another run down the right claims a corner. Chelsea make a mess of the delivery but eventually clear.
Yellow for Ramirez for a late one on Cole.
Credit to both side's in the first half for trying to get the ball down and play despite the testing conditions.
Chelsea start the second half.
Shaw off Clyne on.
The referee blows for half time. Entertaining affair so far, weather playing it's part. 0-0 at the break.
We will have four minutes of time added on in the first half.
Southampton with a dangerous delivery and Cech elects to punch clear.
Cork had earlier made a superb tackle on Ramires.
Great work from Torres again to trick his man but his delivery is weak.
Southampton corner. Ball took a little nick off Cahill.
Great approach play from Southampton but Ramirez's shot is blocked.
CHANCE! Schurrle and Hazard want too much time inside the area and Southampton clear.
Really entertaining game. Southampton with more of the ball but Chelsea look dangerous in the break.
CHANCE! What a run by Ramires and when he approaches the edge of the area Davis is able to flick it over for a corner.
Mikel gives the ball away to Lallana. Ramirez then fouls.
Chambers's ball to Rodriguez is long this time. They are trying that diagonal pass at every available opportunity at the moment.
Schneiderlin playing an important part in front of the Southampton back four. Mikel concedes a foul.
Ramirez from distance but that won't be troubling Cech. Over.
Shaw down the left will get Southampton going again. Lallana looking for little pockets off the strikers.
CHANCE! Chambers leaves Cole for dead and when he cuts back for Lallana his shot is blocked again.
Hazard with a lovely piece of play but Davis is quick off his line again.
CHANCE! All Southampton at the moment. Ramirez with a lovely ball to Rodriguez but he can't bring it down quickly enough. Cole clears.
That's better. Mata this time wins a free-kick.
Chelsea look for Mata but he needs the ball into feet rather than in the air.
Excellent play down the right by Chambers but Cole intervenes and plays it back to Cech to clear.
CHANCE! Torres again. He breezes past two Southampton defenders but his shot is high and wide.
Lovren appears to have got over his early knock as well.
Ramires concedes a free-kick. Southampton on top now.
Lallana looking more lively now. Chambers looks for Rodriguez but his delivery is long.
CHANCE! Lallana does brilliantly inside the area but it's a great block by Cole.
Lovren looking for the long ball towards Ramirez but Terry is coping well at the moment.
Ramires thinks he is clean through after a lovely ball from Torres but Davis is alert and clears.
Game a little scrappy. Stoppages haven't helped.
Azpilicueta appears to have a problem with his back and is making his way off the pitch.
Cork catches Hazard but it was neat play by Chelsea in the build up. Ramires did particularly well.
Chelsea using the ball far better in the early part of this one. Roy Hodgson is here. Few players looking for a World Cup spot.
Lovren is back on but will need to be monitored.
Lovren is now being helped off. Southampton get us started again with a goal kick.
Lovren is still down. Hopefully he will be ok. Southampton will certainly need him.
Concern at the moment on the pitch. Lovren is down with a face injury.
CHANCE! Southampton fail to clear the corner and Schurrle fires wide.
Torres looking really lively early on. This time down the right and he claims another corner for his side.
CHANCE! Southampton give the ball away and Torres does superbly to beat his marker but his shot is deflected wide.
CHANCE! Southampton fail to clear properly. Torres is caught in two minds and pokes wide.
Cole looks long for Torres but Lovren is on hand to clear.
Southampton get us started and away we go. Martin Atkinson is the referee.
Elliot has been in touch via Twitter: "I can see Chelsea just getting a win, helped to victory by an inform Hazard."
The teams are out and we are almost ready to get started. Cracking atmosphere at St Mary's Stadium.
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Chelsea subs: Schwarzer, Kalas, Essien, Oscar, Willian, Eto'o, Ba.
Southampton subs: Gazzaniga (GK), Clyne, Yoshida, Lambert, Ward-Prowse, Hooiveld, Gallagher.
Chelsea starting XI: Cech; Azpilicueta, Cahill, Terry (c), Cole; Mikel, Ramires; Schurrle, Mata, Hazard; Torres.
Southampton starting XI: K. Davis (c), Chambers, Fonte, Lovren, Shaw, Cork, Schneiderlin, S. Davis, Lallana, Rodriguez, Ramírez.
Happy New Year! Welcome to Southampton v Chelsea. Team news to follow...