Chelsea manager Jose Mourinho is unsure of of his Diego Costa's fitness ahead of their English Premier League opener against Swansea this weekend.
Costa suffered a hamstring injury during the International Champions Cup game against Barcelona but Mourinho assured that he will be fit to face in the Charity Shield clash at Wembley.
The 26-year-old however did not play any part in Chelsea's 0-1 lose to Arsenal and also missed yesterday's friendly with and ahead of the EPL opener, Mourinho has admitted that Costa fitness is becoming a concern for them.
"I have to be honest and say that it is a bit of a concern," Mourinho said.
"A player that didn’t finish the season and doesn’t start the season obviously doesn’t make me happy.
'It was a surprise for me he did not play on the weekend. I don’t risk my reputation again. Before the last weekend I told you he’s ready to play. He wasn’t. I don’t know. I don’t risk to say yes but I also don’t risk to say no.
"The boy is trying hard but he has a problem against Barcelona, the next day the scans show there is no injury so the next day he trains but the next day he is not comfortable and 24 hours before the game we don’t know if he plays or doesn’t play.
"It is not a good feeling for him, it is not a good feeling for me.
"You have a minimum of five title contenders and the other teams get stronger and stronger. I think nobody can complain because everyone is investing – you go to , you go to , , , every club."
Watch Diego Costa's goals for Chelsea, below: