Friday 24 October 2014 12:02, UK
Diego Costa was hospitalised earlier this week after contracting a virus, according to Sky sources.
The Chelsea striker has missed his side's last two games, officially with a hamstring injury aggravated while playing for Spain.
But it has emerged the Premier League's top scorer was also ill enough to be hospitalised.
Costa has since been released, and Jose Mourinho is expected to give an update on his fitness when he attends his pre-match press conference on Friday.
Leaders Chelsea go to Manchester United on Sunday, and you can see the game live on Sky Sports 1 HD from 3.30pm.
