SONOMA, Calif. -- Scott Dixon lost 30 potential championship points on what was set up to be a routine pit stop.

Dixon, who entered the GoPro Grand Prix of Sonoma 31 points behind the front-running Helio Castroneves, finished 15th after being penalized by INDYCAR Race Control for a pit safety infraction on his final service stop under caution on Lap 64 of 85 when leading the 25-car field. He heads to Baltimore this week 39 points behind Castroneves, who finished seventh.

The drive-through penalty served on the Lap 70 restart, without recourse by the Target Chip Ganassi Racing team, opened the door for Will Power to win for the first time since Brazil on April 29, 2012. Power is the 10th different winner through 15 IZOD IndyCar Series races (the record is 11 in the 2001 and 2000 CART seasons).

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Power, who started third in the No. 12 Verizon Team Penske car, led Justin Wilson across the finish line by 1.1930 seconds following the last of a race-record seven restarts on Lap 82. Verizon P1 Award winner Dario Franchitti, also seeking his first win of the season, finished third and Marco Andretti was fourth for his sixth consecutive top-10 finish.

Power has won three of the past four races on the 2.385-mile, 12-turn Sonoma Raceway road course, but this one certainly had a different feel.

Dixon and Power were running 1-2 when they pitted on Lap 64, with Power's pit stall directly in front of Dixon's. As the No. 9 Target Chip Ganassi Racing car made its break, it clipped the right-rear tire carried by Penske crew member Travis Law, which knocked him into airjack man Damon Lopez. A third crew member, Jeremy Baker, was struck with an air gun. They were examine and treated in the infield care center and released.

Race Control issued the penalty after multiple video views. Race director Beaux Barfield cited Rule (contact with personnel; under the pit procedures heading) of the IZOD IndyCar Series rulebook in making the ruling.

"Ultimately, we have a duty to protect everybody in the pit lane," Barfield said. "If we have somebody who  uses less than great judgment when they leave their pit box and we have an incident, then we have to make a statement by penalizing. And we're going to make that call. There are a couple of different (video) angles, and clearly the 9 car crosses right into the 12 car's space and that's where the violation occurred. He was in the 12 car's box for a good half-car length."

Dixon, obviously, didn't agree. There were seven penalties issued in the race, including another for a pit safety violation by E.J. Viso (running over an air hose), in the contentious race.

"It's probably the most blatant thing I've seen in a long time," said Dixon, who started on the front row and was seeking his fourth victory in the past five races. "I had a straight line and he walked into us. Pretty annoyed with that; we had a strong car all day."

In the final laps, he charged from 20th to 15th to mitigate the damage. Dixon picked up three bonus points -- two for leading the most laps (27) and one for leading a lap. STANDINGS

Based on qualifications, Power's pit stall will be directly behind Dixon's for the Sept. 1 Grand Prix of Baltimore presented by SRT.

Simon Pagenaud finished fifth and Ryan Hunter-Reay, who is 62 points out of first place, was sixth. Castroneves, driving the No. 3 Hitachi Team Penske car, registered his 11th consecutive top-10 finish.

Thirteen drivers remain in championship contention heading to Round 16 of the 19-race season.

Power, who recorded his 19th career victory, said he "learned a lot about myself" during the drought (he had a best finish of third at Milwaukee this season) and being the championship runner-up the past three seasons.

"When you have a tough year, you really start searching, looking," he said. "You pick up things. Really feels like next year I'll come back more a complete driver. I just kept at it, and just stoked for all the guys that make this possible. It’s great for our confidence and we’re back in our winning ways."

Will Power kisses his winning car