Helio Castroneves converted his third Indianapolis 500 pole position into a third victory in the legendary race, to complete a remarkable comeback following his tax evasion trial.
Only five weeks after he was exonerated by the jury in Miami Federal Court, the Penske driver led home Dan Wheldon - who charged through from 18th on the grid to second for Panther Racing - and Danica Patrick - who became the first female driver to finish in the top three at Indy.
Townsend Bell took a remarkable fourth on a one-off for KV Racing, with Penske's Will Power fifth in what could be his last appearance of the season.
Pitstop issues dropped Ganassi's Scott Dixon and Dario Franchitti, the winners of the last two Indy 500s, back to sixth and seventh after they had dominated much of the event.
The race took time to get into its stride, as the initial start was waved off due to poor formation, and then the yellow came out immediately as dark horse top five contender Mario Moraes made contact with Marco Andretti and speared into the Turn 2 wall, ending both their races.
Franchitti had pounced on one Penske driver by taking Ryan Briscoe at the green, and passed the other at the restart, immediately drafting past Castroneves to take the lead.
He held on to it through the first pitstops, which came early after Ryan Hunter-Reay's miserable month ended when he hit the Turn 4 wall on lap 20 and spun his Vision Racing Dallara into the pitlane.
Castroneves lost out to Briscoe in the stops, and was pushed back to fourth by Dixon shortly after the restart, as the Ganassi/Penske quartet were joined by Tony Kanaan (Andretti Green), Graham Rahal (Newman/Haas/Lanigan) and star rookie Raphael Matos (Luczo Dragon) in a seven-car lead train through the next stint.
Briscoe drafted past Franchitti to take the lead just after quarter-distance, shortly before Rahal's hopes of victory ended when he understeered into the Turn 4 wall while lapping Milka Duno. His team-mate Robert Doornbos did not last much longer before damaging his car in a glancing blow with the wall.
Things went temporarily awry for Penske when racing resumed after Rahal's incident, as Briscoe tumbled off the pace at the green and immediately pitted to replace a tyre that had lost pressure, putting him a lap down.
Castroneves also lost ground as the pack overwhelmed his struggling team-mate, allowing the Ganassi duo to hit the front and dominate the next segment of the race.
Kanaan was their nearest challenger, but his race ended with a massive accident just before half-distance. The Brazilian, who was unhurt despite multiple impacts in the crash, suspected a problem with the rear suspension.
Ganassi continued to run one-two after this incident, but things swung back Penske's way following the next yellow (caused by Nelson Philippe brushing the wall). Franchitti tried to pull away too soon from his stop and fell to 12th as his fuel hose was disentangled, and Dixon lost the lead to Castroneves at the restart, and was passed for second by Power 15 laps later.
A battle for the lead then ensued between the man who started the season in the Penske #3 and the man who reclaimed it from him, as Power set about trying to pass Castroneves.
That fight was paused when Justin Wilson - who had previously escaped a pitlane spin - looped his Dale Coyne car into the Turn 1 wall and prompted the seventh yellow.
Penske remained in one-two formation after the stops, but this time with Castroneves and Briscoe, the Australian having steadily crept back into contention, while Power fell back to sixth behind Wheldon, Patrick and Bell, and Dixon had trouble with a wheelnut and rejoined seventh.
The restart on lap 167 left everyone concerned about whether they could stretch their fuel for a 33-lap final stint, but their strategies were helped by a massive tangle for Vitor Meira and Matos at Turn 1 that saw Meira's car slide along the wall on its side for some distance.
Meira, who had earlier continued despite a dramatic fuel fire at a pitstop, was taken to hospital with back pain, while Matos required assistance getting out of his car. The rookie had run as high as fourth before pitstop delays dropped him into the midfield.
A long yellow ensued as repairs were required to the barriers, and although this eased most drivers' fuel concerns, Penske had short-fuelled Briscoe to help him vault back up the order, and decided to bring him in under caution to fill up, ending his shot at victory.
That left Castroneves ahead of Wheldon and Patrick at the restart, and as the duo behind him went head to head at the lap 183 restart, Castroneves surged away into a clear 1.5s lead.
He continued to edge away for the remaining 17 laps and duly added a third Indy win to his 2001 and 2002 successes, as Wheldon fended off Patrick, Bell, Power and the Ganassi pair for the runner-up spot.
Ed Carpenter took eighth for Vision Racing, with KV's Paul Tracy running in the top ten for most of the day on his return to Indy and taking ninth, ahead of AGR's Hideki Mutoh.
Alex Tagliani (Conquest) came from the final grid position to take 11th, while Briscoe's extra stop consigned him to 15th at the flag.
Pos Driver Team Time 1. Helio Castroneves Penske 200 laps 2. Dan Wheldon Panther + 1.9819s 3. Danica Patrick Andretti Green + 2.3350s 4. Townsend Bell KV + 2.7043s 5. Will Power Penske + 3.6216s 6. Scott Dixon Ganassi + 4.2988s 7. Dario Franchitti Ganassi + 4.9159s 8. Ed Carpenter Vision + 5.5096s 9. Paul Tracy KV + 6.5180s 10. Hideki Mutoh Andretti Green + 7.3312s 11. Alex Tagliani Conquest +10.5351s 12. Tomas Scheckter Coyne +10.9874s 13. Alex Lloyd Schmidt/Ganassi +11.1944s 14. Scott Sharp Panther +11.4259s 15. Ryan Briscoe Penske +12.6695s 16. AJ Foyt IV Foyt +15.4867s 17. Sarah Fisher Fisher +15.9774s 18. Mike Conway Dreyer & Reinbold +16.3488s 19. John Andretti Dreyer & Reinbold/Petty +18.0868s 20. Milka Duno Dreyer & Reinbold + 1 lap 21. Vitor Meira Foyt + 27 laps 22. Raphael Matos Luczo Dragon + 27 laps 23. Justin Wilson Coyne + 40 laps 24. EJ Viso HVM + 61 laps 25. Nelson Philippe HVM + 70 laps 26. Oriol Servia Rahal Letterman +102 laps 27. Tony Kanaan Andretti Green +103 laps 28. Robert Doornbos Newman/Haas/Lanigan +115 laps 29. Davey Hamilton Dreyer & Reinbold +121 laps 30. Marco Andretti Andretti Green +144 laps 31. Graham Rahal Newman/Haas/Lanigan +145 laps 32. Ryan Hunter-Reay Vision +181 laps 33. Mario Moraes KV +200 laps