Four-time series champion Scott Dixon crashed in Indycar's final test session at IMS Raceway on Sunday.
The 37-year-old Kiwi has established himself as one of the modern day greats of the sport and has rarely made mistakes that have resulted in crashes during his 18-year Indycar career.
"It was our second or third lap out of the pits," Dixon said. "A couple of the Andretti cars got by and were a little bit slower.
"I got low in [Turns] 1 and 2, touched the throttle and had a bit of a run and lost the rear. Kind of late in the corner, but just touched with the rear and bent the left-rear suspension."
Indianapolis 500 winner Takuma Sato posted the fastest time of the day, narrowly eclipsing Australian Will Power and Brazilian Tony Kanaan.
The Indycar Series begins next month on the streets of St Petersburg, Florida.
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