MURCIA, Spain (AP) Belgian rider Kris Boeckmans was left in an induced coma after suffering a concussion and facial fractures from a crash during an accident-ravaged eighth stage of the Spanish Vuelta on Saturday.
American Tejay van Garderen also fractured his shoulder in the crash and withdrew from the race along with French sprinter Nacer Bouhanni and Ireland's Daniel Martin, who was third in the general classification.
Jasper Stuyven of Belgium won a sprint finish by a bike length to claim the 182.5-kilometer (113.4-mile) stage in 4 hours, 6 minutes, while Esteban Chaves retained the leader's jersey despite both going down in the accident.
The unexpected pileup in the peloton happened on a straightaway 50 kilometers (31 miles) before the finish of a stage whose biggest threat was supposed to be the sun, not the tarmac.
Boeckmans ended up lying on his side and his Lotto-Soudal team said he was taken to a hospital in the southern region of Murcia.
''The 28-year-old rider has a severe facial trauma with several fractures, he'll probably need surgery,'' the team said. ''Boeckmans also has a concussion, three broken ribs and had a bleeding in his lung. The doctors will now keep him in an induced coma for a few days.''
More trouble came when riders risked too much while veering down a narrow and winding road, before Peter Sagan was knocked down by a motorbike near the finish. Nobody was seriously hurt in those incidents.
Chaves was slowed by the big crash but made his way back to the front to protect his 10-second lead over Dutchman Tom Dumoulin.
''It was a very difficult day,'' Chaves said. ''Before, when you looked at the route, it was supposed to be a so-called transition stage, but it was a day of crashes and falls ... There were nervy, dangerous descents. We are just happy we could keep the red leader's jersey.''
Spanish television showed images of Boeckmans lying completely still while being attended to by medical staff.
''We are all thinking of Kris tonight,'' teammate Tosh Van der Sande said. ''I was riding just behind him when it happened. He was drinking when he rode over a hole, tumbled over his handlebar and hit the ground very hard.''
While Boeckmans was being treated, Van Gardener was on the ground holding his arms across his chest. Before this stage, Van Garderen was in 16th place overall, two minutes behind Chaves. At last month's Tour de France, an illness forced him to quit when he was in third place.
A few minutes later Alex Howes of the United States applied the brakes in time - only to slide into the guardrail while he was briefly leading the race on a breakaway down the steep curves from the Cresta del Gallo hill.
There were also a couple of scary spills on the second descent down the narrow mountain road on the same hill, which the route crossed twice before a final rush to the finish.
Sagan, winner of the third stage, was accidentally taken out by a motorbike with eight kilometers (five miles) left. The Slovak rider got back up apparently unhurt, but televised images showed him kicking a motorbike and yelling at its driver before Sagan rode on.
Sagan's Tinkoff-Saxo team said it is considering ''legal actions against the person or persons responsible for the crash.''
''A Shimano auxiliary motorbike recklessly and dangerously drove into the peloton at high speed hitting Peter Sagan in his rear wheel,'' the team said on its website. ''The unacceptable collision caused Peter Sagan to crash and left the rider with extensive superficial wounds on the left buttocks and leg. Sagan was fortunately able to finish the stage but a final medical examination is yet to be made.''
Despite the turmoil, there were no major changes to the top of the standings other than Martin's exit.
Tour winner Chris Froome remained 1 minute, 22 seconds behind Chaves overall, and also trailing Alejandro Valverde and Nairo Quintana in fourth and six places respectively.
Quintana said that, while the crashes were bad, the heat was brutal.
''More than the nerves, the heat we have been dealing with for the past few days has been inhuman,'' the Tour runner-up said.
Riders get little relief in Sunday's ninth stage, a 168.3-kilometer (104.5-mile) ride from Torrevieja to the Cumbre del Sol or ''Summit of the Sun'' peak.
This story has been corrected to show the first name of Stuyven is Jasper, not Jesper.