May 20 Sebastien Bourdais was transported to hospital for surgery after the French driver suffered fractures to his pelvis and right hip from a crash during qualifying for the Indianapolis 500 on Saturday, officials said.
The former Formula One driver was to be operated on at Indiana University Health Methodist Hospital, IndyCar said in a statement.
The 38-year-old Bourdais, who was driving for Dale Coyne Racing, slammed head-on into the safety barriers when his Honda-powered car lost control at Turn 2.
"Sebastien is in good hands here at IU Methodist Hospital with the staff and now we just wait for him to recover," team owner Dale Coyne said in a statement.
During his first two laps, Bourdais was a full mile per hour faster than the rest of the field at an average speed of 231.534 mph before he crashed into the wall on his third circuit. Qualifying is determined by the average time over four laps.
Bourdais won the season-opening race at St Petersburg, Florida and had the also clocked the fastest time in Friday's practice.
Two-times pole winner Ed Carpenter had the fastest car in Saturday's qualifying for the May 28 race with a four-lap average of 230.468 mph, while double Formula One champion Fernando Alonso was seventh-fastest in his debut race. (Reporting by Larry Fine in New York; Editing by John O'Brien)