Indianapolis — IndyCar driver James Hinchcliffe was taken to a hospital for surgery on his left leg Monday after slamming his car into the wall at Indianapolis Motor Speedway, the fourth frightening wreck during practice for the Indianapolis 500 in the past week.

The Canadian driver hit into the wall going into turn three and his car briefly slid on its right side and almost flipped over before coming came to rest upright. He was removed from the car and IndyCar officials said he had surgery for an injury to his upper left thigh at Indiana University Methodist Hospital, where he was in stable condition late Monday afternoon.

"That was a massive hit," fellow driver Graham Rahal tweeted. "@Hinchtown we're all praying for the best."

IndyCar announced it would resume practice nearly three hours after the crash while it investigated yet another incident that has sharply raised concerns about safety with IndyCar's showcase race coming up on Sunday.

Helio Castroneves and Josef Newgarden went airborne in crashes last week that raised questions about the impact of new oval aero kit packages on the cars. And on Sunday, Ed Carpenter flipped his car on its side in practice leading up to qualifying before IndyCar officials announced changes to reduce power and speeds.

All the cars are using the new aero kits, but Castroneves, Newgarden and Carpenter were all driving Chevrolet cars. Hinchcliffe's car was believed to be the first Honda to have its wheels leave the track's surface during practice.

Hinchcliffe's right front suspension failed, according to Honda spokesman Dan Layton. Layton said Honda officials aren't concerned about the safety of its aero kit, but are more concerned about what caused the suspension problem as the Indianapolis 500 nears.

The four wrecks have been different. Over a five-day period, three drivers hit the walls and all wound up going airborne when they started rolling backward down the track. That wasn't the case for Hinchcliffe.

Derrick Walker, IndyCar's president of competition and operations, has blamed Castroneves' wreck on an aero balance setting that was pushed too far, Newgarden's on a cut tire and said Carpenter simply had an accident.

On Sunday, after Carpenter's crash, IndyCar leaders met with team owners and officials from the two engine manufacturers. They settled on reducing the horsepower, requiring teams to use race setups instead of qualifying trim, not awarding points for qualifying and eliminating the pole shootout.

Scott Dixon of New Zealand took his second Indy pole with a four-lap average of 226.760 mph Sunday — and there were no wrecks


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