The Team Penske driver was running inside the top 10 when his lap belt suddenly popped out and forced him to the pits to be buckled.

It cost him five laps and ended his title aspirations as Chip Ganassi Racing’s Alex Palou went on to win his third title with an 11th place finish.

Power, meanwhile, was 24th and had to pit a second time late in the race after the belt let go again.

“I was just driving down the front stretch there and I just felt a pop on the lap belt,” Power said.

“I was like ‘Man, that’s weird’ and I felt kind of loose in the car in the seat. I came out of Turn 2 and I was feeling around and I felt the end of the belt.

“I’m like ‘Man, my belt just came off, we’re going to have to pit’. It took five laps.

“It happened a second time at the end of the race so we learned real quickly.

“If we had known that… but that’s a very abnormal thing. I don’t know what went wrong. We’ll have to send it back to the manufacturer. Very strange failure.”

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Power feared the worst when the sudden failure occurred, with the potential for injury had he crashed.

“I did wonder if I hit the wall whether it was going to break and I was going to have a real bad situation,” said Power.

“Yep, I’ve never had that before. You have engine failures, you have gearbox failures, and I had a belt failure, so… yeah. Disappointing.”

Power’s lacklustre end to the season saw him fall from second to fourth in the standings behind Andretti Global’s Colton Herta and Team Penske’s Scott McLaughlin.

“Big congrats to Alex, a tough guy to beat, a tough guy,” said Power.

“Ganassi obviously do a fantastic job. It’s been fun racing those guys this year.

“We dropped back to fourth because of this day. Man, if you don’t win, it doesn’t matter.

“I’m happy with the season. The whole team won about half the races. We did well but I want to win that championship. We’ll come back fighting next year.

“We did a great job, winning the Indy 500, winning the most races of any team, I was stoked to win three races this year. It’s a tough series, very difficult to win.

“We’ll come back fighting next year.”