SONOMA, Calif. (Sept. 16, 2016) - The Verizon IndyCar Series championship battle rages to its climax this weekend at the GoPro Grand Prix of Sonoma with two Team Penske drivers vying for the title, but it was a third Penske pilot stealing the spotlight on Friday.

Helio Castroneves led both practice sessions in the No. 3 Hitachi Team Penske Chevrolet, posting a lap in the latter that ranged within half of a second of the Sonoma Raceway track record (Will Power, 1:16.2597, 112.589 mph).

Castroneves' fast lap of 1 minute, 16.6678 seconds (111.990 mph) in the 75-minute afternoon session was followed by teammates Will Power (No. 12 Verizon Chevrolet, 1:16.7072) and Simon Pagenaud (No. 22 Hewlett Packard Enterprise Chevrolet, 1:16.9757).

Power trails Pagenaud by 43 points for the Verizon IndyCar Series championship. With double the usual race points available in Sunday's 85-lapper, Power is the only competitor mathematically eligible to beat the Frenchman, who has led the points since the second race of the season.

Americans Ryan Hunter-Reay (No. 28 DHL Andretti Autosport Honda, 1:17.0569) and Alexander Rossi (No. 98 Castrol Edge/Curb Andretti Herta Autosport Honda, 1:17.0817) rounded out the top five on a day when Andretti Autosport backed up its pace shown in testing at the 2.385-mile road course last week.

Rossi's day ended prematurely when he stopped on track at the start/finish line, ending the session a few minutes early. Prior to that, Dale Coyne Racing's Conor Daly (No. 18 Jonathan Byrd's Hospitality Honda) suffered a mechanical failure that also brought out a red flag.

The third and final practice session ahead of Verizon P1 Award qualifying begins at 11 a .m. PT on Saturday. Verizon P1 Award qualifying airs live at 3 p.m. Saturday on NBCSN. The season-concluding GoPro Grand Prix at Sonoma Raceway begins Sunday at 3:30 p.m. on NBCSN.

Tickets are still available for the GoPro Grand Prix of Sonoma, and kids 12 and under are admitted free all weekend. In addition to the Verizon IndyCar Series, the weekend also features the Formula Car Challenge and Pirelli World Challenge Series. For more information, visit or call 800-870-RACE (7223).