Chelsea back on top after Diego Costa's winner.

This could turn into THE greatest Premier League title race of all time.

Have a read of Jonathan Jurejko's match report

We are back tomorrow as West Brom take on Burnley.

Until then.

Middlesbrough have now lost their last six Premier League games against Chelsea, failing to score in each match.

Chelsea

Chelsea boss Antonio Conte tells the BBC: "I am very proud but we must know we have to continue in this way. 

"I told the players we must start well after the international break and I think we had the right concentration to win a tough game. 

"I knew this game would be difficult because this team is well organised and they are in good form. But we deserved to win because we scored the goal and created many chances for a second goal. 

"The first five minutes wasn't good for us. Middlesbrough started very well and we started badly but during the game our possession got better and we started to move the ball quicker. Also we didn't concede and stopped any opportunity for them to score. 

"The league doesn't finish today but it's the first time we have lead this season. 

"It's not going to be easy but we must be happy for our hard work and commitment. Now I will tell our team we have work to do."

Matchwinner Diego Costa became the first player to reach double figures for Premier League goals this season and has netted seven goals in his last seven away games.

Middlesbrough

Middlesbrough manager Aitor Karanka tells Sky: I am really pleased with the attitude of my players. We knew it was going to be hard but we are in the Premier League and one mistake gets you punished. 

Diego Costa is one of the top scorers in the world. Before the game I said to my players you can't lose him for one second and they lost him. 

I am not worried about the look of the league table at the moment because all I am concerned about is the performances. If the performances were bad I would worry but if the performances are good then we will start to win games. 

Middlesbrough defender Ben Gibson tells BBC Sport: "We stayed in the game and fought until the end, we could not get a point. We are really disappointed to be beaten by a set piece. A lot of positives to take.

"In the second half, we got out of the blocks quickly and made a game of it. they were not comfortable by any means. We can take a lot of heart and positives out of this.

"We have played Manchester City, Arsenal and Chelsea and we have come out of each one with a lot of merit. We are a tough squad and we will stick together. Playing those giants, we still believe we can get something from the games.

"We limited Diego Costa and dealt with him quite well. He is tough, wants to wrestle you and feel you but he finished his one chance."

Chelsea wing-back Victor Moses tells Sky Sport: "We showed good character from the start, we had a few chances in the first half which we should have taken.

"In the second half, they came at us and we were strong at the back. We did very well today.

"I am delighted and excited to be in the first 11, the new manager wants to give the youngsters an opportunity to express themselves.

"The top is very tight. The Premier League is a hard season and we want to take each game as it comes."

Chelsea defender Gary Cahill tells Sky Sports: "Confidence is up in the side and we are playing well. We are getting the results too which is the most important thing. We have carried on from where we left off at the int break.

"We are in a good moment on the training ground and working hard. When you are winning games, it is easy to play.

"We are happy with today's work, the league is not won today, it is not even Christmas yet."

Pat Nevin
Ex-Chelsea winger on BBC Radio 5 live

Not the best game Chelsea have ever played but they got the win they needed. 

You could maybe argue they deserved it during those attacking moments but they lacked slightly in the quality of passing. Middlesbrough could have taken it from them a few times. 

They got the result and that's all they will care about. 

Image source, Getty Images

Chelsea boss Antonio Conte is enjoying this victory.

He makes his way onto the pitch and gives each player a rib-tickling hug.

Image source, Reuters

Diego Costa's goal is enough to take Chelsea top of the Premier League table.

Pat Nevin
Ex-Chelsea winger on BBC Radio 5 live

Image source, Reuters

Eden Hazard has put in a hell of a shift but he has not has his best game. 

You always come to see a player like him play - you want to see something extra special but he had a couple of knocks early on which seemed to slow him down a little I think. 

Antonio Barragan plays a pass forward from right-back...

...straight out of play at the other end.

What a waste.

Thibaut Courtois not exactly sprinting to get the ball back into play.

Middlesbrough striker Alvaro Negredo upends David Luiz and concedes a free-kick.

Into the final minute of injury time...

Eden Hazard now making his way off for a breather.

Oscar, who has grown or is attempting to grow a beard, comes on.

Seconds ebbing away for Middlesbrough to try and get a point from this game.

The 90 minutes are up.

FOUR minutes of added time to play...

A change for each side late on.

Chelsea boss Antonio Conte sends on Branislav Ivanovic in place of the impressive Victor Moses.

Boro boss Aitor Karanka has given Grant Leadbitter a runout for Adam Forshaw.

Alan Green
BBC Radio 5 live

Image source, Getty Images

Middlesbrough, from their body language, clearly feel that they can get an equaliser still. 

Adama Traore gets on his skates again and sprints past N'Golo Kante before feeding Stewart Downing on the left, but no team-mate can get on the end of the former England international's cross...much to the dismay of the home supporters.