The Daily Mail is reporting that the 25-year-old midfielder has suffered an inflamed Achilles tendon in his right leg and he has been replaced in the squad by Mijo Caktas.
Kovacic featured for 83 minutes of Chelsea FC’s 2-2 draw with Sheffield United at Stamford Bridge on Saturday before he was replaced by Michy Batshuayi.
Chelsea FC fans will be hoping that Kovacic’s injury setback is not too serious and that he will be able to make himself available for the Blues’ clash with Wolves away from home on 14 September.
The midfielder, who joined on a permanent deal from Real Madrid this summer after having spent last season on loan at the club, has started three of Chelsea FC’s four Premier League games so far this term.
He notched up an assist for the Blues during their 3-2 win over Norwich City.
Chelsea FC currently find themselves in 11th place in the Premier League table after having taken just five points from their opening four Premier League games.
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