Chelsea manager Jose Mourinho has revealed that he won't make a decision on Diego Costa's fitness until after training on Friday afternoon.

Costa returned to West London earlier than scheduled after picking up a hamstring injury while with Spain, but after a week of treatment, Mourinho has insisted that the forward is in contention to face Swansea City on Saturday.

The 51-year-old told reporters: "Diego came back injured but that was last Saturday so we had one week to work hard with the medical department and he has a chance to play tomorrow.

"We have a training session now to confirm his condition, but he was the only one that came back from the national team with a problem."

Costa has netted four goals in his first three appearances since signing from Atletico Madrid in the summer.