Antonio Conte has denied suggestions that Diego Costa is on his way out of Chelsea, claiming that the striker is "very happy" at the club.
The Spain international was thought to be close to joining former side Atletico Madrid this summer after a £40m bid was tabled.
Conte himself admitted last week that he was unsure whether Costa would remain a Chelsea player in the long-term but, having now got the 27-year-old back to full fitness, there is hope that he will remain in place.
"Diego has recovered from his injury and now he is available for tonight's game against AC Milan," the Evening Standard quotes Conte as saying.
"I will decide the formation, the starting XI today. But he is available and I am very happy that I can count on him. I repeat that Diego Costa is now Chelsea's player and for me this is the most important thing in this moment.
"It is an opportunity to see him play against AC Milan. I repeat, Diego is Chelsea's player and he is very happy to stay with us."
Costa, left out of Chelsea's squad for the 3-2 defeat to Real Madrid, scored 10 goals in a disappointing season for the Blues last time out.