Australis's reigning world champion Casey Stoner may not get a chance to defend his Indianapolis Grand Prix title after a crash-filled day on Saturday.
And Nicky Hayden won't get to race in front of his home fans.
Stoner, last year's pole winner crashed in qualifying, will be re-evaluated Sunday morning after doctors finally decided he had "small, marginal" fractures in his right ankle.
American Nicky Hayden crashed and went flew into the air. Series officials said Hayden regained consciousness and was taken to a hospital for a CT scan.
After Stoner's motorcycle wobbled, he tried to regain control but flew over the handlebars and across the grass. He tried to walk back to his bike, but called a medical team over and was taken away on a stretcher.
Originally, doctors thought Stoner had broken his right ankle - an injury that probably would have ended his chance of becoming the race's first two-time winner.
The 26-year-old Stoner, who is racing for the final time in the US this weekend, could still be cleared to ride Sunday.
If he does, he'll start sixth on the 23-motorcycle starting grid after completing the 16-turn, 2.621-mile road course in 1 minute, 39.465 seconds. Hayden's teammate with Repsol Honda, Spain's Dani Pedrosa, won the pole with a time of 1:38.813.
Stoner, a two-time world champ, already announced he'll retire after this season. He wasn't the only rider struggling to tame Indy's slick track.
Valentino Rossi, the most successful MotoGP rider in history, explained why there were so many slips and falls as riders prepared for Sunday's races.
"This asphalt don't have a lot of grip, but at the same time, creates very much temperature on the tire," he said. "And Bridgestone brings some tires harder on the edge."
With about eight and a half minutes left in the 60-minute qualifying session, Hayden had an even scarier crash. The Ducati rider wobbled coming through a turn, then spun sideways, launching into the air and somersaulting across the track before coming to a stop in a prone position.
Without the crash, he would have started eighth after posting a fast lap of 1:39.748.
About four minutes before Hayden's crash, American Ben Spies, the 2010 Indy pole winner, slid off his bike and went rolling through the dirt. He got up, made it back onto the track and will start fourth. Following practice, Spies went to the infield track centre for more evaluation.
Earlier, Hector Faubel of Spain flew off his bike during qualifying for the Moto3 race. A spokeswoman for the Bankia Aspar team said the rider went to the hospital with bruised ribs and an injured back.
And Hector Barbera, who crashed during Friday morning's MotoGP practice, is heading home to Spain for more tests after fracturing three vertebrae - two of which were broken in a 2008 crash. Toni Elias, the Spaniard who won 2010 Indianapolis Moto2 winner, replaced Barbera on the No. 24 bike Saturday and qualified 17th for the Pramac Racing Team.