Indy 500 practice: Rahal tops Wednesday session, Hildebrand crashes

Rahal had played down a perceived lack of speed ahead of the practice session and went fastest early in the day's session.

In a day of little movement up and down the timesheets, Rahal's best speed of 226.047mph proved the fastest.

The session's final 20 minutes were notable for the first non-track inspection caution of the week when JR Hildebrand got high out of Turn 3 and collided with the wall on the exit of Turn 4.

He damaged the rear of his car and moved to the infield before he was later cleared from the medical centre without injury.

No true fast laps were set in the final 10 minutes, so AJ Foyt Racing driver and one-time Indianapolis 500 winner Tony Kanaan ended the session second ahead of Wednesday pacesetter Marco Andretti.

Ed Carpenter and Sage Karam were fourth and fifth ahead of Penske's Josef Newgarden.

Zachary Claman De Melo continued preparations for his maiden Indy 500 in place of Pietro Fittipaldi with the seventh-fastest lap.

Helio Castroneves was a late mover to eighth fastest, completing the most laps of any driver with a total of 110 as he builds towards attempting to win the race for a fourth time.

Ed Carpenter Racing's Spencer Pigot was ninth ahead of Harding Racing's Gabby Chaves.

Penske's Simon Pagenaud was 11th ahead of a late improvement from Scott Dixon in his Chip Ganassi Racing-run car.

Pagenaud's team-mate Will Power set the 13th fastest time overall, but his 223.971mph lap without a tow was unbeaten.

Notable drivers lower down the timesheets included Dale Coyne Racing's Sebastien Bourdais in 15th, seven places ahead of Andretti's Alexander Rossi.

Schmidt Peterson Motorsports driver Robert Wickens was two places further back from Rossi in 24th, with Andretti's Ryan Hunter-Reay 26th.

Danica Patrick worked her way from the rear of the field up to 30th, one place ahead of James Hinchcliffe in the 35-car field.

Defending Indy 500 winner Takuma Sato was 33rd.

IndyCar testing resumes with 'Fast Friday', which is expected to give some indication of the pace that drivers will hit in this weekend's qualifying.

Thursday practice times