Chelsea striker Diego Costa required hospital treatment following his side's penalty-shootout defeat to Stoke City in the League Cup after sustaining a rib injury.

The Spaniard was forced off after 32 minutes following a challenge by Charlie Adam, making him a fitness doubt for this weekend's Premier League clash with Liverpool.

"He is in the hospital - I don't know," Chelsea manager Jose Mourinho told reporters when asked whether Costa faces a spell on the sidelines.

Reports suggest that Mourinho could be sacked if his side loses against Liverpool on Saturday.