Championship weekend kicked off with a 3.5 hour practice session.
With Justin Wilson in everyone's thoughts, IndyCar teams got back to work on Friday with a three hour and 30 minute practice session at Sonoma Raceway.
Will Power, who is still eligible for the title (but a long shot), led the way with a best time of 1:17.4858. The reigning champion was followed by the man with the best shot to take the crown from Juan Pablo Montoya - Graham Rahal.
Pocono winner Ryan Hunter-Reay was third, Scott Dixon fourth and Marco Andretti fifth. Helio Castroneves, sixth, ran the most laps at 59 total. Points leader Montoya timed in ninth quickest.
There are 25 cars on the entry list with Russian driver Mikhail Aleshin making his IndyCar return - he was 17th.
The lone red flag was Oriol Servia, driving the No. 25 Andretti Autosport Honda in place of the late Justin Wilson. He stopped on track, but the yellow flags were quickly cleared.
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