Reigning NASCAR Sprint Cup champion Jimmie Johnson claimed his first ever-road course victory at Infineon Raceway after Australian Marcos Ambrose handed him the lead in bizarre circumstances.
The Hendrick Motorsports driver had stated before the weekend started that he was "irritated" by not having won a non-oval event yet, claiming he had worked hard to get better at his road course technique.
All his effort came to fruition on Sunday afternoon at Sonoma but not without some help from former Australian V8 Supercar champion Ambrose, who looked set to claim his maiden Sprint Cup win until his car stopped while running behind the pace car under caution.
Johnson had been dominant in the first part of the race, leading from lap one to 33 until he pitted for the first time under green. He would get back in front once the stops cycled through and after passing Red Bull's Mattias Ekstrom, who was running a different pit stop strategy in the early going.
However, following his last stop for fuel on lap 79, Johnson remained behind Ambrose, who pitted a lap after him. From then on the JTG Daugherty racer looked in control, keeping the current champion at bay before the unexpected happened.
When the seventh caution of the day came out for an incident involving Penske's Brad Keselowski, Ambrose coasted behind the pace car, turning off his engine at times to save fuel. While going up the hill after Turn 1, his car did not fire back up and he rolled to a halt before Turn 2.
He was eventually able to get his engine restarted, but by then he had been passed by at least six cars, and NASCAR officials deemed he had failed to maintain "reasonable speed" behind the pace car, placing him back in seventh place for what turned out to be the final restart of the race.
"I didn't think at first that he had shut the car off going up the hill. That's just the last place you would probably do it," said Johnson, who was untouchable in the final sprint. "So, I thought maybe he ran out of fuel or had an electrical problem, you know, something major, because the car just came to a stop. I'm like, 'Wow!'
"I just didn't really think that he would be the one to make a mistake. I was going to push and do what I could. To see the mistake happen as it did was totally off the wall. I don't know if I've ever seen that eliminate a guy from winning a race."
Robby Gordon managed to get the best out of his strategy to finish second, pitting a number of times under the fourth caution to eventually go the distance without an additional stop, which most of the leaders completed later under green.
He had to fend off Richard Childress Racing's Kevin Harvick in the closing laps, to claim his best result of the season and get a much-needed boost in the owner standings.
Behind Harvick, who ran a clean race to retain the points' lead, Richard Petty's Kasey Kahne charged back following a poor first stint from pole to finish in fourth place.
Jeff Gordon rounded out the top five after an eventful race, which saw him take part in a number of incidents while trying to make progress through the field. Ambrose eventually finished behind him in seventh, followed by Greg Biffle.
Sonoma regular Boris Said led the race for a few laps but was hit by Keselowski on the fourth restart. Said salvaged an eighth place ahead of Tony Stewart, who led the race at one stage, making it to the checkered flag on two stops only, while most of the top runners stopped at least three times for fuel and tires.
Earnhardt Ganassi's Juan Pablo Montoya was down in 33rd with less than 25 laps to go after additional stops for fuel and tires, but made the most of his grip advantage to finish 10th in the end.
After winning the previous two races, Denny Hamlin had a day to forget, getting caught in a number of incidents, including a multi-car crash on a restart on lap 68, which forced the race to be red flagged for more than 20 minutes to clean the wreckage on the start-finish stretch.
Jan Magnussen wrapped up a good Sprint Cup debut by finishing the race in 12th place for Phoenix Racing, while Red Bull's Mattias Ekstrom was 21st in the end, following a late incident with Keselowski while fighting for a top 10 finish.
Pos Driver Car Laps
1. Jimmie Johnson Chevrolet 110
2. Robby Gordon Toyota 110
3. Kevin Harvick Chevrolet 110
4. Kasey Kahne Ford 110
5. Jeff Gordon Chevrolet 110
6. Marcos Ambrose Toyota 110
7. Greg Biffle Ford 110
8. Boris Said Ford 110
9. Tony Stewart Chevrolet 110
10. Juan Pablo Montoya Chevrolet 110
11. Dale Earnhardt Jr Chevrolet 110
12. Jan Magnussen Chevrolet 110
13. AJ Allmendinger Ford 110
14. Mark Martin Chevrolet 110
15. Jamie McMurray Chevrolet 110
16. Ryan Newman Chevrolet 110
17. Elliott Sadler Ford 110
18. Scott Speed Toyota 110
19. David Gilliland Ford 110
20. David Reutimann Toyota 110
21. Mattias Ekstrom Toyota 110
22. Paul Menard Ford 110
23. Bobby Labonte Chevrolet 110
24. Travis Kvapil Ford 110
25. David Ragan Ford 110
26. JJ Yeley Dodge 110
27. Jeff Burton Chevrolet 110
28. Kevin Conway Ford 110
29. Carl Edwards Ford 110
30. Matt Kenseth Ford 110
31. Clint Bowyer Chevrolet 110
32. Kurt Busch Dodge 110
33. Joey Logano Toyota 108
34. Denny Hamlin Toyota 103
35. Brad Keselowski Dodge 102
36. Sam Hornish Jr Dodge 93
37. Dave Blaney Toyota 86
38. Regan Smith Chevrolet 86
39. Kyle Busch Toyota 76
40. Joe Nemechek Toyota 71
41. PJ Jones Toyota 68
42. Martin Truex Jr Toyota 66
43. Max Papis Toyota 65