Team Penske’s Josef Newgarden has beaten David Malukas to victory by half a second in a thrilling conclusion to the Gateway IndyCar race.

After a rain delay of more than two hours, it was a 36-lap green flag run to the finish, and Newgarden quickly passed team-mate Scott McLaughlin for the lead upon the restart.

However, Dale Coyne Racing rookie Malukas emerged as a genuine threat to the #2 and #3 Chevrolets, and would snatch second from McLaughlin at the start of the 260th and final lap.

He took the chequered flag just 0.4708s behind Newgarden, with McLaughlin third, from Pato O’Ward (McLaren SP), Takuma Sato (DCR w/ Rick Ware Racing), and series leader Will Power.

The result means that Power’s margin atop the points table is down to three, with Penske team-mate Newgarden moving into second, and Chip Ganassi Racing’s Scott Dixon only 11 points further back in third spot after finishing eighth on the night.

Power took pole and led initially, from Ganassi’s Marcus Ericsson, McLaughlin, and Newgarden.

Dixon took up fifth but was soon passed by O’Ward while Alex Palou (Ganassi) was shuffled from sixth to ninth in a handful of laps.

Power’s margin ebbed and flowed in traffic but he got to two seconds up on Ericsson on Lap 50, by which time O’Ward had just taken fourth spot off Newgarden.

Ericsson assumed first place when the rest of the top five pitted on Lap 59, although he was in a lap later.

The Swede lost position to McLaughlin in the pits before being passed by O’Ward on the blend, meaning an order of Power, McLaughlin, O’Ward, Ericsson, Newgarden, and Dixon.

Newgarden rounded up Ericsson on Lap 89 through Turn 1, and briefly headed O’Ward when the Mexican’s failed attempt to pass McLaughlin for third on Lap 91 almost resulted in him crashing instead.

Power had just crept a second clear of McLaughlin when both stopped on Lap 124, and the #12 crew ensured the Queenslander stayed ahead of the Kiwi in the #3 Chevrolet.

Sato, however, had come from sixth to undercut his way to a lead of two seconds over Power by the time the latter passed Romain Grosjean (Andretti Autosport), who had been running long.

McLaughlin would assume third, from O’Ward, Ericsson, Newgarden, and a slightly earlier stopping Dixon.

O’Ward dived past McLaughlin for third at the start of Lap 136, by which time Sato had pushed his margin over Power beyond five seconds.

The figure was six seconds up when a Caution came on Lap 145 due to ninth-placed Jack Harvey (Rahal Letterman Lanigan Racing) hitting the wall at Turn 4 as he tried to lap Ed Carpenter (Ed Carpenter Racing).

When pit lane opened, McLaughlin was in from fourth and Newgarden from sixth, but Sato took another lap before peeling off.

Power stayed out and led O’Ward, Ericsson, Dixon, Palou, McLaughlin, Newgarden, and Sato, the only eight still on the lead lap when the yellow came.

When the race restarted on Lap 158, O’Ward charged around the outside of Power at Turn 1/Turn 2, while McLaughlin quickly passed Dixon and Palou to move up to fourth.

Newgarden was on an even bigger charge, taking advantage of traffic to pass Ericsson and then McLaughlin, before blazing past Power as they ran into Turn 3 on Lap 164 and then rounding up O’Ward with relative ease.

He was two seconds to the good on Lap 168, by which time McLaughlin had overtaken Ericsson for fourth, and six seconds clear of O’Ward on Lap 174.

McLaughlin passed Power on Lap 175, then was down the inside of O’Ward for second place at Turn 1 on Lap 177.

Dixon kicked off the next pit stop cycle on Lap 189, with Power in from fourth on Lap 194 and O’Ward from third on Lap 197.

Meanwhile, after Newgarden’s margin peaked at just over seven seconds, McLaughlin would start to slash that gap, with some assistance from traffic.

They were separated by 1.7s when the New Zealander took his fourth stop on Lap 206, and the #2 crew responded by calling Newgarden into the pits a lap later.

Crucially, he appeared to be held up as he followed Christian Lundgaard (RLLR) into the lane and McLaughlin would breeze past as the two-time champion rejoined the race track.

The cycle had just completed when a Caution was called on Lap 215 in response to the light rain which had finally come.

McLaughlin led from Newgarden and O’Ward, who had been 10 seconds off the pace prior to the yellow, then Power, Malukas (DCR w/ HMD Motorsports), Sato, Ericsson, and Dixon.

The yellow was upgraded to a red flag after two more laps, as rain got heavier and lightning struck in the area.

It would take more than two hours before the field was sent back out again to complete the final 43 laps.

There was a nervous moment for Newgarden when Car #2 initially did not re-fire, but his crew eventually got him underway just in time to re-take second position in the queue.

Ericsson, Dixon, and Palou ceded track position when they pitted before the restart, although only to eighth through 10th respectively, behind Rahal.

When the green flag flew on Lap 225, Newgarden got a run on McLaughlin and made the pass for the lead as they ran into Turn 3.

Behind, Malukas used the benefit of his newer tyres, and a little help from traffic, to finally pass Power for fourth on Lap 231.

The #12 Penske driver also lost position to Sato at that moment, although it could have been much worse given they made contact as they flashed down the back straight.

McLaughlin was staying in touch with Newgarden as Malukas put O’Ward under pressure, which he turned into an overtake for third spot on Lap 244.

He was three seconds from the lead then but caught Newgarden and McLaughlin with around 10 laps to go.

As they took the white flag, Malukas stormed around the outside line and prised second from Car #3.

McLaughlin would finish a second back from Newgarden and Malukas, with O’Ward another 3.7s in arrears in fourth and Sato rounding out the top five.

The rest of the top 10 was Power at six seconds further behind, then Ericsson, Dixon, Palou, and Rahal.

Alexander Rossi was classified 25th at 34 laps down after the #27 Andretti Honda ran dry and struggled to re-fire during his second pit stop.

Rinus VeeKay bumped the pit wall right at the start but it was an electronics problem for the #21 ECR Chevrolet which meant he would not be running at the finish.

Just two events remain this season, the next at Portland on September 2-4 (local time), with coverage live and ad-free on Stan Sport.

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Results: Race, Gateway Motorsports Park

Race winner: 260 laps

Series points