Danica Patrick used a fuel gamble to take a historic victory in the delayed Motegi round of the IRL IndyCar Series.
The Andretti Green Racing driver took the lead with just two laps to go as the rest of the front-runners had to pit for fuel, and became the first woman to win a major American open-wheel race.
Patrick had run on the fringe of the top six for most of the race, as Ganassi's Scott Dixon and Penske's Helio Castroneves dominated the event.
But AGR's decision to bring Patrick in for an additional fuel top-up at the end of the final full course yellow paid off spectacularly, allowing her to take a remarkable last gasp victory.
Castroneves led the first half of the race - which was postponed by a day due to poor weather earlier in the weekend - with Dixon, Dan Wheldon (Ganassi) and Tony Kanaan (Andretti-Green) in close pursuit.
Dixon jumped into the lead during the second pitstops, and was then able to pull away from the field, leading by as much as six seconds.
But the final yellow on lap 142 eliminated his advantage, and left all the teams in a fuel mileage quandary.
While most hoped in vain for additional yellows, Patrick, Castroneves and Vision Racing's Ed Carpenter all chose to make an extra stop just before the green, but only Patrick was able to conserve enough fuel in the final 51 laps to make it to the flag.
She duly rose to the front as Dixon, Wheldon, Kanaan, and Carpenter all had to pit within the final six laps, while Castroneves slowed dramatically as his car ran all-but-dry, falling to second behind the victorious Patrick.
Dixon completed the podium after his pitstop.
Wheldon and Kanaan claimed fourth and fifth ahead of Carpenter - who had charged back into the lead group after earlier being delayed in a pitlane tangle with teammate AJ Foyt IV.
Ryan Hunter-Reay finished seventh for Rahal-Letterman Racing, with Foyt's Darren Manning in eighth and Ryan Briscoe surviving a late brush with the wall to take ninth for Penske. The Australian had vaulted from the midfield to the lead group by topping up his fuel under an early yellow and consequently having a rapid second stop, but fell out of contention for the win when he scraped the wall in the closing laps.
Townsend Bell claimed the final top ten spot for Dreyer & Reinbold.
While Patrick celebrated a momentous victory, two of her Andretti-Green Racing teammates had less happy afternoons. Second row starter Marco Andretti spun into the wall at the first corner of the race, while local favourite Hideki Mutoh could only finish 11th after spinning in the pit exit and almost crashing into the pace car.
Pos Driver Team Laps
1. Danica Patrick Andretti-Green 200
2. Helio Castroneves Penske 200
3. Scott Dixon Ganassi 200
4. Dan Wheldon Ganassi 200
5. Tony Kanaan Andretti-Green 200
6. Ed Carpenter Vision 200
7. Ryan Hunter-Reay Rahal-Letterman 200
8. Darren Manning Foyt 199
9. Ryan Briscoe Penske 199
10. Townsend Bell Dreyer & Reinbold 199
11. Hideki Mutoh Andretti-Green 199
12. Buddy Rice Dreyer & Reinbold 198
13. Jay Howard Roth 192
14. Roger Yasukawa Beck 134
15. AJ Foyt IV Vision 103
16. Vitor Meira Panther 92
17. Marty Roth Roth 44
18. Marco Andretti Andretti-Green 0