Will Power secured victory in a tense and thrilling race at the IndyCar Grand Prix to claim Penske's 200th series win.
The Australian driver led the field away at the start and remained there until after the first round of stops, where he battled with rookie Robert Wickens, as the pair traded alternating tyre strategies until the final stint.
Many drivers preferred the red-striped alternate softer tyre throughout the race while the primary, harder black tyres struggled for pace and durability, setting up a finely-poised run to the flag.
On lap 56 out of 85, Penske's Josef Newgarden tried a lacklustre overtake on Sebastien Bourdais and this led to the American spinning and stalling the car to bring out the final caution which meant the frontrunners were forced into a fuel-saving battle towards the chequered flag.
Scott Dixon stormed through the field to finish in second-place after a poor qualifying session on left the No.9 Ganassi/Honda in 18th place while Wickens in the No.6 Schmidt Peterson entry struggled in the final stages of the race with fuel saving and had to settle for the final spot on the podium.
Four-time series champion Bourdais kept his nose clean in throughout the race despite the close-call with Newgarden; the Frenchman's No.19 Dale Coyne car managed to steal fourth place away from Long Beach race winner Alexander Rossi in the final laps.
Helio Castroneves returned to IndyCar in preparation for his attempt to win a fourth Indy 500, despite having done some testing with the new aero kit earlier on in the season, the Brazilian appeared to struggle against the full-time runners but managed to bring his Penske home in sixth place.
After qualifying fourth, James Hinchcliffe was unable to match the race pace of his Schmidt Peterson team-mate and could only manage seventh place at the chequered flag.
Simon Pagenaud put in a solid effort to come back and clinch eighth place after he was hit into the Turn 2 gravel trap on the opening lap by the No.20 Ed Carpenter entry of Jordan King.
Graham Rahal also made up for a poor qualifying session to score a ninth-placed finish ahead of RLL racing team-mate Takuma Sato, the Japanese driver had a rough start to the race after he was hit by a flying Spencer Pigot on the opening lap in Turn 5 and forced onto the grass and dropped towards the back of the field.
Reigning champion Newgarden trailed home 11th after his error, but holds onto the series lead, a mere two points clear of Rossi.
Tuesday will see the teams and drivers begin practice for the 102nd running of Indianapolis 500.
