Blues fear summer arrival could be set for lengthy spell out.
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Chelsea face being dealt a major injury blow with the news that summer signing Diego Costa could miss six weeks of action with a hamstring injury, according to the Daily Telegraph.
The 25-year-old sustained the problem in training this week, and although the full extent of the problem is not yet clear, it could mean that Jose Mourinho’s side will be without their impressive new centre-forward for some time.
Costa has been in fine form since his £32m move from Atletico Madrid this summer, scoring two goals in as many games so far in the Premier League, and looking like solving what has been a problem position for the club in recent years.
Veteran striker Didier Drogba is available as cover, while out-of-favour Spaniard Fernando Torres may also find himself back in the first-team fold after failing to even make the bench for last weekend’s clash against Leicester City.
Costa had some bad luck with injuries for Atletico last season, limping off in the Champions League final defeat to Real Madrid.