Chelsea's run of four games without a win comes to an end. Diego Costa's seven games without a goal is over. You can feel the relief around Stamford Bridge.
- Chelsea: Begovic, Ivanovic, Zouma, Terry, Kenedy, Matic, Fabregas, Pedro, Willian, Hazard, Diego Costa.
- Norwich: Ruddy, Wisdom, Bennett, Bassong, Olsson, Howson, Mulumbu, O'Neil, Brady, Redmond, Mbokani.
Former England defender on Final Score
"Normally Chelsea go 1-0 up and you think that's it, it's over. But they look vulnerable now and are under pressure here still."
Ramires runs into the corner to eat into time. Seconds remain.
Into injury time. Norwich desperately piling forward, Chelsea holding on. Two minutes of added time to go.
Standing ovation for Eden Hazard as he is replaced by Cesar Azpilicueta. He fully deserves it as well. He's put a proper shift in.
Another Chelsea change sees Willian go off and Ramires on.
The home fans chant Jose Mourinho's name. He's still got their backing. And he'll keep it as well as long as they keep winning.
Norwich are still in this game, but only because of John Ruddy. The keeper pulls off a superb save to deny Nemanja Matic, who had danced into the box and given himself just the keeper to beat.
Off goes Pedro, on comes Oscar. Not bad to have such players in reserve. How Alex Neil would love to be able to chuck on a player of the Brazilian's class.
When you’re chasing the ball it’s so difficult to keep pressuring and getting back behind the ball, this will be mentally tough for Norwich as they try and get back into the game.
No sign of the changes making any difference for Norwich. They are pinned back, unable to get anywhere near the Chelsea goal. Another Blues goal looks the more likely.
Cue an equaliser now!
Pedro shot, just wide. It was a decent effort from 20 yards that flew just past the post.
Chelsea look far more confident now. Nemanja Matic gets forward but his low cross from the left is cleared by Ryan Bennett.
Three changes for Norwich. Yes, three. On come Wes Hoolahan, Graham Dorrans and Cameron Jerome. Off go Jonny Howson, Youssouf Mulumbu and Dieumerci Mbokani. It is Alex Neil's first, second and last throw of the dice, all in one.
That’s just down to pure quality from Costa, he steps inside Ryan Bennett who over committed himself. That is a lot of relief for the fans, players and manager here at Chelsea.
Another Norwich man - Martin Olsson - goes into the book for a foul on Diego Costa as he looked to break into the box. This gives Willian a great position to deliver a free-kick.
Oh, Norwich almost level as Robbie Brady shoots from 25 yards and draws Asmir Begovic into a fingertip save to put it past the post. Branislav Ivanovic rises high to head the corner away.
Chelsea almost make it 2-0 as Willian's free-kick is flicked onto the bar by the boot of Kurt Zouma.
Former England defender on Final Score
"There is no real celebration from Diego Costa. It is very much job done, as if to say I know I've had my chances and should have scored already. It was more relief."
Former Spurs striker on Final Score
"Whatever the speculation is around Diego Costa supposedly leaving Chelsea in January, he buries this. And what I like about it is, he is cold about the finish. He take his time, turns inside the defender, and slots it home."
Breakthrough. Norwich's stubborn resistance is finally broken as quick thinking from Cesc Fabregas sends the ball forward to Diego Costa via a free-kick. the striker cuts inside Ryan Bennett and curls a low shot into the far corner. Fabregas assist, Costa goal. So familiar last season, but so rare in this. It has done the job for the Blues today.
It’s 'heart in mouth' time for Norwich, it looks like Chelsea may score at any moment. But credit to City they are sticking to the task well.
Once again, Eden Hazard is stopped illegally, this time by a shirt-pull from Sebastien Bassong, who goes into the book.
Now Nemanja Matic tries his luck from range. It flies high and wide.
Soon after, Eden Hazard cuts to the byline on the right and crosses low between the Norwich defence and keeper. Again, there isn't a blue shirt in sight.
The home crowd are not happy.
Cesc Fabregas goes alone with a shot from range, but he doesn't catch it right and John Ruddy is able to dive to his left to save low down. It is testimony to Norwich's discipline that there was nothing else on.
Jose Mourinho stands on the sideline, concern etched across his face.
Former Nottm Forest boss on BBC Radio 5 live
"The one thing Chelsea haven't done is managed to sustain any attacking pressure. You have to credit Norwich, they have been nice and compact but still.
"Certainly Kurt Zouma should have done a lot better with that effort - that counts as a good chance in games like this."
If Chelsea are going to get a goal, you suspect Eden Hazard will be involved. The midfielder gets to the byline again and digs out a cross, which has the Norwich defence stretching to head clear with two Chelsea players waiting in the box.
It is all Chelsea at the start of this half. A block from Jonny Howson wins them a corner which finds Kurt Zouma but his volley flies well over. He had plenty of space to do much better.
Chelsea have another free-kick, this time from wider right as Willian is tripped by Robbie Brady. The Brazilian takes again but his delivery is cut out by the head of Jonny Howson.
Willian does take the free-kick and beats the wall but not John Ruddy, who collects the ball with ease.
Gary O'Neil resorts to illegal measures to stop Eden Hazard, tripping the midfielder as he looked to receive a one-two from Diego Costa in the Norwich half. It gives Chelsea a free-kick (Willian anyone?) and earns the Canaries player a yellow card.
We are back under way at the Bridge.
A very entertaining 45 minutes comes to an end. Chelsea will be frustrated. They have had most of the ball but have been held at bay. Norwich have been disciplined and defensive but committed when they have broken. They have arguably had the best chance of the half, forcing John Terry into a superb block from Sebastien Bassong's shot.
Into the final moments of the half and Chelsea pile forward. Kenedy is in an advanced position and sets up Diego Costa but his shot is blocked. The ball goes behind off a Norwich man but there won't be time for the corner...
What a challenge from John Terry! The Chelsea defender throws himself in front of a Sebastien Bassong shot in the box following a corner and prevents his side conceding.
Then, straight down the other end, John Ruddy proves equally heroic for his side to block a goal-bound shot from Diego Costa with his boot.
That is the best 30 seconds of the match.
The referee is making some bold decisions, is he trying to even things up after Norwich’s penalty shout? Bassong was all over him but Costa did go down easily.
A penalty shout for Chelsea now as the ball is fed into the feet of Diego Costa who looks to get past Sebastien Bassong and falls under a challenge. The defender was using all his strength to try and keep the striker from a shot. Was it an illegal attempt to stop him? I don't think so. The Spaniard just wasn't strong enough.
Eden Hazard has done most of his work down the left so far, but now he pops up on the right to produce a superb run and pull-back from the byline. It fizzes straight across the six-yard box. Where was Diego Costa?
“I though it was a penalty, Robbie Brady is going towards goal, Willian comes from nowhere and knocks him off the ball"
Sam: That move has summed up Chelsea this season. Great build up by Hazard but once again Costa not delivering. Torres saga all over again!
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Big shouts from the away side for a penalty as Robbie Brady goes down in the box under a challenge. The referee is firm in his rebuttal. Nothing illegal about that tackle according to Craig Pawson.