TIGNES, France -- Defending champion Tadej Pogacar kept control of the Tour de France on a rain-soaked second day in the Alps as a crash-filled opening week took its toll on rivals on Sunday.
"I'm sure a lot of guys suffered today," said Pogacar, who retained the race leader's yellow jersey by responding when required in the ninth stage.
Both last year's runner-up Primoz Roglic and former overall leader Mathieu van der Poel dropped out of the race before the grueling 144.9-kilometer (90-mile) route from Cluses to Tignes.
Australian rider Ben O'Connor won the stage after launching a solo break with 17 kilometers to go. Sergio Higuita was unable to follow the 25-year-old as O'Connor powered up the Col du Pré for the finish at Tignes.
O'Connor struggled to fight back tears after his first tour win.
"Just to be taking part on the Tour de France in the first place is a dream. Then to achieve a victory like this one is excellent, a great reward to everyone who has supported me over the years," O'Connor said. "It's been a wild ride."
O'Connor finished more than five minutes ahead of Mattia Cattaneo and Sonny Colbrelli. Pogacar responded to a late attack by Richard Carapaz to defend his overall lead by finishing sixth, just over six minutes behind O'Connor.
UAE Team Emirates rider Pogacar has a lead of 2:01 over O'Connor in the general classification ahead of the first rest day on Monday.
Pogacar had doubts toward the end of the stage.
"I was scared that I might lose the yellow jersey just the day before the rest day," Pogacar said. "I'm happy to keep it."
Van der Poel held the yellow jersey for six days but relinquished it to Pogacar on Saturday.
"We decided with the team that it's in my best interests to quit the race and focus on the Olympics now," the Dutch rider said after pulling out.
Roglic crashed badly during Monday's third stage in the western Brittany region and had been struggling since. The Jumbo-Visma team said the Slovenian rider would focus on new goals.
"We took the decision all together with the team, it doesn't make sense to continue," Roglic said.
Roglic performed well in Friday's time trial, but suffered in the 151-kilometer (94-mile) route from Oyonnax to Le Grand-Bornand on Saturday, when Pogacar seized control of the race. Roglic was already almost 40 minutes behind his compatriot before Sunday's stage.
Roglic said he surprised himself in the time trial but doubts returned in the first mountain stage Saturday when he was in a lot of pain.
"It's just too much for my body at the moment and yeah, I cannot race," the 31-year-old said. "I'm disappointed. I didn't plan it to be the way it is, but in the end, I have to accept it."