Everton full-back Tony Hibbert will miss the start of the Premiership season after contracting a tropical disease while on holiday.
The club's medical staff initially thought Hibbert's symptoms were caused by a simple stomach bug, but had to re-evaluate their diagnosis when his condition got worse.
Subsequent tests revealed his problems are down to the rare cryptosporidium parasite.
Head physio Mick Rathbone told the club's official website: "It's the first time for me. It seems Tony has picked up a parasite presumably when he was on his holidays.
"It is not that common, and the experts' advice is that he should fight it off himself. There is no actual treatment for it. But he should, in time, fight it off.
"It may take days or weeks. We don't really know. We see Tony every day and he seems a lot better every day. But he hardly ate for seven to ten days and he isn't eating that much now.
"He lost in excess of half a stone so he is not imminently going to return."