The 25-year-old is believed to have pulled up in training on Wednesday afternoon after straining his hamstring and the Guardian newspaper claim the initial prognosis appears to indicate the striker is set for a spell on the sidelines.
Costa is expected to undergo further tests at Chelsea’s Cobham training base today and no doubt Jose Mourinho will be praying the injury isn’t as bad as first feared, as if the strain is confirmed he’s set to miss up to six weeks.
The Brazilian-born striker has settled well following his £32m move from Atletico Madrid earlier in the summer, having scored in each of his first two appearances in the Premier Leagueagainst Burnley and Leicester.
It looks like Costa is certain to miss the upcoming trip to Goodison Park to face Everton, but if he’s ruled out for any period of time, then it could have a barring on the future of Fernando Torres.
The Spaniard is being tipped to leave Stamford Bridge this summer with AC Milan showing a keen interest, but Mourinho may have to re-think letting him leave if Costa’s injury is confirmed.
The Blues boss could decide to still let Torres go, but it would mean a late dash into the transfermarket to bring in another striker during the final four days of the window.