Driver James Hinchcliffe working his way back after a concussion

In this May 18, 2014 photo James Hinchcliffe, of Canada, talks with a crewman after his qualification run for the Indianapolis 500 IndyCar auto race at the Indianapolis Motor Speedway in Indianapolis. A week ago, there were questions that Hinchcliffe would be able to race in the Indianapolis 500 after suffering a concussion in the Grand Prix of Indianapolis. The 27-year old Canadian is not only cleared to drive, he's second on the grid for the most famous race in IndyCar (AP Photo/Tom Strattman) (The Associated Press)

In this May 18, 2014 photo James Hinchcliffe, of Canada, returns to the pit area after his qualification run during qualifications for the Indianapolis 500 IndyCar auto race at the Indianapolis Motor Speedway in Indianapolis. A week ago, there were questions that Hinchcliffe would be able to race in the Indianapolis 500 after suffering a concussion in the Grand Prix of Indianapolis. The 27-year old Canadian is not only cleared to drive, he's second on the grid for the most famous race in IndyCar (AP Photo/Tom Strattman) (The Associated Press)

WEST ALLIS, Wis. – While awaiting medical clearance to resume driving after a concussion, James Hinchcliffe's thoughts of competing in the Indianapolis 500 went from apprehension to appreciation.

"It was the not knowing, that was the hard part," said Hinchcliffe, who qualified second for the 500 after being cleared to return.

"As a racing driver, we're all control freaks basically, and not knowing and having your future in someone else's hands like that in a sense, it was very nerve-wracking."

Hinchcliffe sustained a concussion when struck in the head by debris from another car in the inaugural Grand Prix of Indianapolis on May 10. He missed five days while waiting to be cleared and then qualified second, despite limited practice time.