Antonio Conte is refusing to consider Chelsea Premier League title favourites despite seeing them climb to the top of the table with victory at Middlesbrough.

Diego Costa's first-half strike secured a 1-0 win at the Riverside which extended the Blues' recent run to six league victories, all of them negotiated without conceding a goal.

But, asked if they are now title favourites after leapfrogging Liverpool and Manchester City, Conte said: "Now it's very difficult to reply to this because if you see the recent past only one and a half months ago and see that Chelsea had two defeats against Liverpool and Arsenal.

"After these two games, Chelsea wasn't a favourite or a team that could fight for the title until the end.

"Now it's very difficult to change completely that opinion. I think we are working very well, but if you ask me what is our target now, I repeat it is very difficult to tell you this.

"I want to wait until the end of the first part of the championship."

Chelsea manager Antonio Conte (centre) celebrates their win at the Premier League match at Boro

Chelsea have now played 590 minutes of top-flight football since their 3-0 defeat at Arsenal on September 24 without conceding, and that too is something Conte admits he could not have predicted.

He said: "I am pleased because in this league, it is very difficult to have this success and to win these six games in a row is fantastic."

Asked if his team was the best in the country on current form, Conte was equally coy.

He said: "When you arrive at a new club after a bad season like last year, you don't know what the response of the players will be because you lose a bit of confidence in your capacity.

"I am pleased because I know and also the players and our fans know Chelsea must fight until the end for something. But if you ask me if I was sure about this at the start of the season, it's very difficult."

Boro gave as good as they got for long periods in the game and, with goalkeeper Victor Valdes in inspired form, might have emerged with something to show for their efforts.