World champion Dai Greene has pulled out of tonight's Diamond League meeting in Rome due to illness.
Greene, who was due to compete in the 400 metre hurdles in the Stadio Olimpico, revealed on Twitter that he was "gutted" at being forced to withdraw with a virus.
"So disappointed to say this but I'm no longer racing tonight. Woke up not well. Been in bed all day as feel so bad. Gutted," the 26-year-old Welshman said.
"My apologise (sic) to the meet organisers and people expecting to see me race. Such a horrible decision to make but have to be sensible.
"Hoping to recover quick to get back to training for the olympics. Just want to be home."
Greene began his season by competing in Rabat on Sunday, where he finished second in 48.96 seconds. He is expected to compete in next week's Diamond League meeting in Oslo.
The reigning world, European and Commonwealth champion will be looking to complete his set of major championship gold medals at the Olympics in August.
Britain's Perri Shakes-Drayton then also withdrew from the women's 400m hurdles race as a precaution due to a minor hamstring strain.
But at least Greene's withdrawal should mean a place in the men's event for training partner Jack Green, who had been first reserve.