Paracyclist Alex Zanardi is in intensive care after colliding with a truck while participating in the "Obiettivo tricolore" relay race in Siena. Zanardi, who suffered serious head and nerve injuries in the accident, underwent surgery Friday night and is in a coma.

The 53-year-old handcyclist, a four-time Paralympic gold medalist, was riding with former road pro Daniele Bennati on Friday afternoon when they lost control on a downhill and collided with a truck on the other side of the road.

Since being airlifted to the University Hospital of Siena, Zanardi has undergone nearly three hours of "neurosurgical and maxillofacial (jaw and face) treatment" and is currently in "stable but serious" condition in the intensive care unit.

According to a press release issued by the hospital Saturday morning, Zanardi's "hemodynamic and metabolic parameters are stable. He is intubated and supported with artificial respiration, but his neurological status remains critical.

Italian national para-cycling coach Mario Valentini, who was following the race in a minivan, added that Zanardi overturned on a downhill near Pienza and the track tried to avoid him.

"The stage ended in Montalcino and we were almost there," he told Corriere della Sera (open in new tab). "It was a curve, a not too difficult descent, and we were going about 50 kilometers an hour. Alex lost control of his handbike, overturned twice, and collided with a truck.

"The impact was severe and very serious. Paramedics were able to contain him, but the helicopter was unable to land.

Giuseppe Oliveri, the hospital's neurosurgery director, gave an update on Zanardi's condition Saturday.

"He arrived with facial fractures and a depressed fracture of the frontal bone," Olivieri told Corriere della Sera (open in new tab).

"He must remain sedated and on artificial respiration, waiting for the secondary damage from the trauma to stabilize over time.

"If he improves, it will be very slowly over time. An assessment of the neurological situation will be made when he wakes up. It is useless to speculate what will happen today. I am just absolutely convinced that he is absolutely worth treating."

Local prosecutors have opened a criminal investigation into the accident and are looking into the organization of the race and the safety measures in place at the time. The driver of the truck is also under investigation, and Chief Prosecutor Salvatore Vitello has denied any alcohol or drug influence, stating that it was a necessary precaution.

Zanardi, who competed in Formula One and the American CART series in the 1990s, famously overcame life-threatening injuries in 2001 when he lost both legs in a CART crash at the Lausitzring in Germany.

During his long recovery from the crash, Zanardi helped design his own prosthetic limbs and eventually returned to auto racing, competing and winning the World Touring Car Championship from 2005 to 2009.

Zanardi's second sporting career was hand cycling, which he began in 2007. Since then, he has enjoyed great success in cycling, winning marathons in Venice, Rome, and New York, 12 Paracycling World Championships, and four gold medals at the London and Rio de Janeiro Paralympics in 2012 and 2016.

Daniele Bennati expressed his support for Zanardi on Instagram on Friday: I still can't believe it and no one else does. Just before that damned half-curve, you said. 'Guys, today is one of the best days of my life. We are all with Alex. "

Italian Cycling Federation President Rocco Di Renato also wished Zanardi well (opens in new tab) and said, "His example is a source of inspiration for many of us and now is the time to let him feel all the warmth of our world."

Italian Prime Minister Giuseppe Conte (opens in new tab) and UCI President David Lapartiento also added messages of encouragement on social media.

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