Newgarden worked his way past fellow Penske drivers Scott McLaughlin and poleman Will Power to grab the lead just before half distance of the 250-lap race.
That proved to be the key move, with Newgarden staying out front for his first win since the Indianapolis 500 in May – and to keep up his 100% record on ovals this year.
Power led the field to green, leading team-mates McLaughlin and Newgarden. Scott Dixon (Chip Ganassi Racing) held fourth, with Colton Herta (Andretti Autosport) and Pato O’Ward (Arrow McLaren) duelling straight away for fifth, with the latter grabbing the spot by lap three.
Dixon attacked Newgarden for third on lap five, but the six-time champion soon had the charging O’Ward all over him, the Mexican getting ahead after a dozen laps. Behind O’Ward, Alex Palou (Ganassi) got the hammer down and rose to fifth by lap 30, bringing the battling David Malukas (Dale Coyne Racing) and Marcus Ericsson (Ganassi) forwards too.
Dixon and Herta fell back, clearly struggling with their tyres, and it was so bad for Herta that he made his first stop on lap 41. To make matters worse, his right-front wheelnut got crossthreaded and he lost four laps.
By the one-fifth distance mark, Power led McLaughlin by half a second, with Newgarden 2s further back. O’Ward was best of the rest, ahead of Palou, Malukas, Ericsson and Dixon.
O’Ward was the first of the leaders to pit on lap 58, with Power, McLaughlin and Newgarden stopping three laps later, allowing Palou to lead for a lap before he pitted too.
Power cycled back to the front, still clear of McLaughlin, with Newgarden slipping back by 5s in third but happy with the changes they made in the pitstop.
O’Ward held a distant fourth, with Ericsson and Ganassi team-mate Takuma Sato moving up to fifth and sixth, as Palou dropped back to ninth after the first round of stops. Dixon was another tumbler, now a lap down in 15th.
Josef Newgarden, Team Penske Chevrolet
Photo by: Josh Tons / Motorsport Images
McLaughlin attacked Power for the lead on lap 83, as they came up to lap Romain Grosjean’s 12th-placed Andretti car. Newgarden then joined in the lead battle, grabbing second from McLaughlin on lap 95 as the Penskes lapped the cars at the bottom end of the top 10.
Newgarden began to attack Power on lap 101, but he had to be careful of the lurking McLaughlin as the Penske trio continued to dominate by almost 10s.
Newgarden got another run as Power toiled to lap seventh-placed Alexander Rossi (McLaren), who had surged up from 20th on the grid.
Newgarden grabbed the lead from Power on lap 121, after the Aussie slipped up the track in Turn 2.
The second round of pitstops unfolded right on the stroke of half distance, with Newgarden rejoining ahead of Power.
Ericsson briefly jumped up to third, having pitted early, but McLaughlin soon dealt with him on fresher rubber, and O’Ward also passed the Swede by lap 131.
Early leader Power began to struggle on this stint, dropping to fourth on lap 145 after glancing the wall exiting Turn 4.
That gave Newgarden – who had now lapped everyone up to sixth place – a 6.5s lead over McLaughlin, with O’Ward a second further back but closer to the leaders than he’d been for a while.
That became irrelevant when the first caution of the race flew, for Graham Rahal hitting the Turn 4 wall far harder than Power and breaking the right-front corner of his Rahal Letterman Lanigan Racing car.
“Legitimately the worst car I’ve ever driven on an oval,” he reported. “A major rethink is needed overnight.”
Earlier strategy gamblers Ericsson and Kyle Kirkwood (Andretti) had their prayers answered, and were now ensconced in fifth and sixth respectively, and the yellow also meant that the five cars behind them (Palou, Rossi, Dixon, Sato and Grosjean) got their lap back.
The race restarted on lap 167, with Ericsson jumping ahead of Power immediately. O’Ward attacked McLaughlin, but couldn’t make it by, while Power re-passed Ericsson.
The race quickly settled down, however, with some fuel saving reducing the pace to keep strategy options open with the finish in sight.
Newgarden extended a 7s lead over McLaughlin, who in turn was well clear of O’Ward, who had Power, Ericsson, Kirkwood, Palou and Dixon on his tail.
The leaders made their final pitstops from lap 208, rejoining in the same order up front, but Ericsson muscled past Power to take fourth with 39 laps to go. Meantime, Dixon got ahead of Kirkwood for sixth, as Palou slipped back to eighth.
McLaughlin got the gap to Newgarden down to less than 2s on the final stint, but the leader was managing his gap and minding the traffic (he lapped everyone up to fifth) – despite a few nervous moments in the closing laps.
O’Ward finished a distant third, ahead of Ericsson, Power and Dixon and Kirkwood. Points leader Palou finished a lap down but will view eighth as a decent result for damage limitation.