IndyCar has placed Graham Rahal on probation for six races for his role in an accident with Marco Andretti.

IndyCar race director Beaux Barfield says Rahal was both blocking and initiated avoidable contact on the 22nd lap of Sunday's race in Long Beach, Calif. Andretti ran into the back of Rahal's car, and the contact caused Andretti's car to briefly launch into the air and spin into a barrier.

Andretti said after the accident that Rahal had chopped him, and added, "I'm lucky I didn't get upside down. I could have been killed."

Rahal denied chopping in front of Andretti.

Barfield said a review of the accident by all of IndyCar's stewards determined Rahal had endangered on-track safety and adversely affected competition.

Both drivers declined to comment Tuesday.

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