RIO DE JANEIRO (AP) — Irish cyclist Nicolas Roche says he developed a serious case of bacterial pneumonia while in Brazil to compete in the Olympic road race and will be forced to miss the Vuelta a Espana.

Roche suggested on Twitter that he may have gotten sick from a “bad aircon in Rio,” though he did not say how he knew that it was caused by air conditioning, nor did he specify whether it was from a unit in the Olympic village.

“Riding the Vuelta was a big target for me this year and I was looking forward to being part of the team,” Roche said. “The illness couldn’t have come at a worse time, really, and after speaking to the medical staff, it’s pretty clear that I’m not going to be ready in time.”

Roche competed in the road race in support of countryman Dan Martin on the first full day of competition at the Rio Games. He finished 29th after dropping a chain on the base of the final climb.

His trade team, Team Sky, confirmed Roche will miss the Vuelta a Espana due to the illness.

The potential for illness has been a major concern in Rio, though mostly because of the Zika virus and issues with water quality.

The Vuelta a Espana is the third of cycling’s three Grand Tours, following the Giro d’Italia and the Tour de France. And it was the one Roche has been targeting most of the season, building toward not only the Olympics but also the mountainous race in Spain.

Roche said he was “gutted” to miss the race, which begins with a team time trial Aug. 20. Doctors have prescribed eight full days of rest before Roche can get back on a bike.

He hopes to be able to compete again before the end of the season.

“Obviously it’s a big disappointment. The Vuelta is a race I really enjoy and one where I have had success before,” he said. “I’ll be focusing on my recovery and getting back as soon as I can.”

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