Conte: Costa One Of The Best  (Sky Sports)

Antonio Conte says Diego Costa is "one of the best strikers in the world" after he fired Chelsea to the top of the Premier League.

The Spaniard's 10th goal of the season helped the Blues to a 1-0 victory over Middlesbrough at the Riverside Stadium - their sixth in succession in the league without conceding - and moved them ahead of Liverpool and Manchester City in the table.

Costa's temperament has been questioned at times since moving to Stamford Bridge in 2014, but Conte has been delighted with the 28-year-old's attitude and told the striker to carry on doing what he is doing.

"For me, it's important to have this type of question because in the past, you asked me about his behaviour, about his reaction, about his patience," Conte said.

"Now I think he is one of the best strikers in the world and he has to continue in this way, showing his patience, but in the right way.

"He is very focused on the team, to help the team with the ball, without the ball and he is scoring a lot of goals. He has to continue so."

The new league leaders host Tottenham next Saturday ahead of the busy Christmas programme, but Conte is prepared for what lies ahead.

"We are ready, we are ready to play many games in few days because from the start of the season, we have worked a lot, not only on the tactical aspect, but the physical aspect," Conte said.

"We continue to work because, in this league, it's important to have in every game high intensity, to have strength and to run from the start until the end - and also to have good technique and good talent."

Costa's 41st-minute close-range strike ultimately separated Chelsea and Middlesbrough, with Victor Valdes and the woodwork keeping Boro in it until the death, although Aitor Karanka's men were unable to take advantage of a series of half-chances which came their way to grab a point.

Alvaro Negredo forced the one meaningful save Thibaut Courtois had to make, but struggled to emulate Costa's influence at the other end of the pitch. After the game his manager was asked how the lone frontman could contribute further.

Karanka said: "Going in the way he is going, working as he is working, fighting as he is fighting against everybody, and knowing he is not playing for Chelsea or Manchester City, he is playing at Middlesbrough and he is not playing with the team-mates that he's had in the past or the team-mates Costa has at Chelsea."