Chelsea striker Diego Costa was reportedly sent to hospital after the international break with Spain due to illness.
The 26-year-old is a doubt for this weekend's Premier League showdown against Manchester United, having missed the Blues' last two games with a hamstring problem.
Reports have claimed that a groin injury is now troubling the prolific striker, but it is also understood that Costa was forced into hospital recently with an apparent severe stomach bug, according to The Telegraph.
Costa, who reportedly did not train yesterday ahead of Sunday's encounter, has scored nine goals for Chelsea so far this season.
