Premier League: Jose Mourinho reckons Diego Costa will soon be scoring goals for Chelsea again

Diego Costa: Chelsea striker has hamstring problems

Chelsea boss Jose Mourinho is confident Diego Costa will start scoring again when the striker's fitness improves.

The Spain international scored seven goals in his first four Chelsea appearances following his arrival from Atletico Madrid in the summer.

But Costa has netted only twice in his last seven games, having been hampered by hamstring problems.

And the Spain international has been overtaken as the Premier League's leading scorer by Sergio Aguero of Manchester City.

Mourinho's men suffered their first defeat of the season at Newcastle on Saturday, with Costa failing to find the net for the third game in a row, but the Chelsea boss is backing the player to come good.

"For me, the problem is not the goals - they will come as a consequence of his condition,” Mourinho said.

"He has to improve his condition. He was injured and had many doubts because he went a long time without training.

"Obviously that must have an effect on a player in the way he runs, the way he moves and in his co-ordination.

"I don't think there is any problem but he has to recover."

It remains to be seen whether Costa will be given the chance to build his match-fitness in Wednesday's Champions League clash with Sporting Lisbon, as Chelsea have already qualified for the knock-out stages.