Sir Bradley Wiggins has withdrawn from the Giro d'Italia after suffering from a chest infection.
The Team Sky cyclist, one of the pre-race favourites, was five minutes and 22 seconds down on the leader. But he will be aiming to recover from the illness in time to race at the Tour de France in July.
Wiggins was aiming to become Britain's first ever winner of the Giro d'Italia. Last year he became the country's first winner of the Tour de France, and he was targeting the Italian race this season, with Chris Froome set to lead the team in France.
But Team Sky boss Sir Dave Brailsford confirmed Wiggins will not be able to continue.
As reported by the BBC, Brailsford said: "His chest infection has been getting worse and our primary concern is always the health of our riders.
"Bradley will return to the UK today for treatment and to rest, and we hope to have him back on the road as soon as possible.
"As a passionate racer he wanted to continue but he is simply unable to do so on medical grounds."
Italian rider Vincenzo Nibali leads the race, with Team Sky's Rigoberto Uran well-placed in third two minutes and four seconds behind the leader.
Wiggins was 13th before the withdrawal, after a fall on stage seven on a wet road set him back. A combination of mechanical problems and poor conditions also hindered his chances of winning his specialist event - the individual time trial on stage eight.
The Giro d'Italia defending champion Ryder Hesjedal of Team Garmin-Sharp has also pulled out ahead of stage 13.