Briscoe crashes in Indy 500 practice

Ryan Briscoe and Team Penske are scrambling to get his backup car up to speed after he crashed during practice for the Indy 500.

The rear end of Briscoe's car hit the wall hard on Saturday morning, less than three hours before qualifying began. He was taken by ambulance to the Indianapolis Motor Speedway's medical center. He was diagnosed with a bruised left knee and was cleared to drive by track medical officials.

Briscoe says the crash was caused by cold tires. But he made it back on the 2.5-mile oval in a backup car with about 20 minutes left in the final practice.

Briscoe's fast lap during practice was 225.101 mph - the 26th fastest of the session.

Pole qualifying for the race on May 29 begins later Saturday. Twenty-four spots on the 33-car starting grid are expected to be filled.