Diego Costa Injury: Updates on Chelsea Star's Hamstring Injury and Return

Chelsea striker Diego Costa is starting the Blues' season opener against Swansea City, the team announced ahead of kick-off on August 8.

The striker suffered a hamstring injury during the Blues' pre-season match with Barcelona in Washington, D.C on July 28.

Speaking to the Alan Brazil Sports Breakfast show on talkSPORT, manager Jose Mourinho expressed concern about Costa's status, saying:

"

I have to be honest and say it is a bit of a concern. A player that didn't finish the season and doesn’t start the season obviously doesn’t make me happy.

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.

"

The 26-year-old was a hit for the Blues during his first season in the Premier League, scoring 20 league goals. Costa gave Chelsea's attack the kind of dynamic scorer it was missing during the previous season, combining well with Eden Hazard.

He arrived at Stamford Bridge with some injury concerns, which dogged him all year. Mourinho admitted in March the Spain international has problems staying healthy, per Mark Ogden of the Daily Telegraph.

Any further setbacks will put the onus on summer loan signing Radamel Falcao, but Costa remains the Blues' attacking focal point when fit.

Chelsea will be strong favourites to retain the Premier League title this season, and they'll be delighted to have Costa fit for the opening league game of the campaign.