"It's a good result for Panther Racing and the National Guard - to finish fourth here with this level of competition is something we can build on," Wheldon acknowledged, "I always tended to lose a few places on starts and restarts but, once the car came in, it was as good as anybody out there.

"Toward the end of the race, I should have made some more aggressive changes with the front wing, because I had some understeer, but my race was relatively low key. I was loose at the start of each stint, but once the car settled down it was good, and I'll take a top five."

Dixon's event was spoiled early on when his Ganassi entry was tagged by 'polewinner' Helio Castroneves. The Brazilian had started from the front of the pack based on entrant points after qualifying was cancelled due to water seeping onto the track. Both cars were forced to pit for repairs.

"We tried to go with two different strategies, and it looks like Dario just had a stellar day," the Kiwi commented, "Once we touched [with Castroneves], we cycled back and, once we got back in traffic, it was really tough. We should have done much better, but at least one of the cars did well this weekend."

Castroneves eventually finished an understeer-afflicted seventh, with Tomas Scheckter posting the best result since his return to the fray with sixth for Dreyer & Reinbold Racing. The South African combined with eighth-placed rookie Mike Conway to give DRR a rare double top ten, last achieved at last year's Indianapolis 500 when Buddy Rice finished eighth and Townsend Bell tenth.

The race got off to a rough start with four caution periods in the first 55 laps, but finished with stints of 56 and 127 consecutive green flag laps.

EJ Viso was again a first lap casualty, spinning in unison with Robert Doornbos but damaging his HVM car against the outside wall and being forced to retire. Doornbos pitted with damage but, after a lot of work, returned to the track. The handling on his Newman/Haas/Lanigan entry was compromised, however, and the Dutchman called it quits atfer a cumulative 58 laps.

The race's other retirements - for Ryan Hunter-Reay, Justin Wilson, Raphael Matos, Mario Moraes and Kanaan were all the result of contact.