Will Power continued to set the pace in the lead-up to this weekend's IZOD IndyCar Series race at Sonoma after setting the fastest time in Saturday's second practice session. Power, who led Ryan Briscoe in a Penske one-two during Friday practice, secured the top spot with a fastest lap of 1m17.5339s.
For much of the session nobody was able to get within 0.7sec of the Australian's time before Ganassi's Scott Dixon finally managed a 1m17.9725s effort. Briscoe and Dario Franchitti both improved their times late in the session to finish up third and fourth fastest, respectively, roughly half a second off Power's time, with Sebastien Bourdais keeping Helio Castroneves out of fifth.
James Hinchcliffe prompted the morning's sole red flag with a spin at Turn 11, although the Andretti Autosport car was undamaged and the Canadian was able to complete the session.
Qualifying follows later this afternoon.