He was among the top 10 during qualifying before he crashed.
"The brake just went to the floor," Power said after he was cleared from the infield care center. "I think the fronts were working so it was a brake failure on the rear. That’s all I know."
Power maintained that the car was still good despite not having a "clean lap" during the race weekend so far. He will start 23rd when it’s time to go green on Sunday.
Scott McLaughlin also had a serious crash during practice. He spun out going into a turn and backed his car into the fence at 150 mph.
He said after the crash that it looked a lot worse than it felt. He managed to bounce back a bit during qualifying and will be starting in 14th.
Alex Palou won the pole position with David Malukas, Graham Rahal, Marcus Armstrong and Kyle Kirkwood rounding out the top five.
The race is set to begin at 1 p.m. ET on Sunday and can be seen on FOX and FOX One.
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