A stop-start opening to the race ended in domination for the Captain’s team, with Power heading Josef Newgarden and Scott McLaughlin.

Linus Lundqvist led the field from pole at the race start before team-mate with Marcus Armstrong nosed into the back of his Chip Ganassi Honda. In the ensuing melee, Colton Herta was tagged by Newgarden as they checked up.

It scattered the field as the Caution was predictably thrown.

Under the stoppage, Kyle Kirkwood led from McLaughlin, Alex Rossi, Newgarden, Scott Dixon, and Power.

Racing resumed at the start of Lap 4, McLaughlin immediately taking the lead into Turn 1.

It was a brief green flag period, little more than a lap, as the Caution was called for after Herta’s car shed some of its diffuser exiting Turn 1.

That had followed a clash with Lundqvist at Turn 4 at the restart, which potentially contributed to the debris Herta deposited.

A strategic faux pas from McLaren saw Pato O’Ward pit to replace his alternate tyres at the end of the opening lap, a move designed to check the tyre requirements box.

However, drivers must complete two laps on the alternate rubber, meaning the Mexican would have to bolt the red-walled tyres back on at some point.

McLaughlin led the restart on Lap 6 but again it was brief when Kyffin Simpson crashed out on Lap 7.

The Chip Ganassi driver was punted by Christian Rasmussen, pitching his rival into the concrete wall and retirement, Rasmussen handed a stop-go penalty for his part in the incident.

A number of drivers pitted under the Caution, Herta among them, taking on a new set of primary tyres.

It was also an opportunity for the team to assess the damage to the rear of his car, the Andretti squad working to effect whatever repairs they could.

Racing resumed at Lap 10, McLaughlin accelerating prior to Turn 14 to hold a useful gap as he took the green while Kirkwood in second was forced to defend from Newgarden, who had the option tyres fitted.

Quickly the pack began to string out, McLaughlin leading Kirkwood by 1.2s on Lap 12 and Newgarden a further second back. Power ran fifth, 3.8s away from the lead and half a second back from Rossi.

Theo Pourchaire pitted after 15 laps to swap off the option tyre, the first driver to make a proper racing stop.

McLaughlin was in from the lead next time by, triggering a host of others to follow.

Penske kept McLaughlin on the primary tyres as Newgarden remained on track, inheriting the lead as Kirkwood also pitted.

Newgarden was in after 18 laps, as were Power and Dixon, and emerged in the lead but, at racing speed, McLaughlin was able to sneak by at Turn 1 to reclaim top spot.

Alex Palou went a lap longer still, remaining on the primary tyres as he cycled out in third, ahead of Kirkwood, but dropped to fourth as he exited Turn 2, and fifth when Dixon out-dragged him exiting Turn 3.

Herta, Felix Rosenqvist, and Lundqvist remained on track and held the top three places, but all were off sequence to the bulk of the pack.

Herta stopped from the lead at the end of Lap 22, feeding back in behind a train of cars that ran from Dixon in 10th back to Ferrucci in 16th.

Struggling for grip, Dixon was swamped as he dived for the pits, followed by Armstrong, having been dumped from 10th to 24th in the process.

The Kiwi had suffered severe blistering on his left-rear tyre, Romain Grosjean mugging him at The Kink which triggered Dixon being freight trained by the queue of cars in his wake.

After 25 laps, McLaughlin headed Newgarden by 3.6s, with Power third, Palou fourth, and Kirkwood in fifth.

The race then settled down in the run to the second round of stops, beginning with Rinus Veekay stopping from ninth place after 28 laps of racing.

It was some three laps earlier than the leaders had planned, though O’Ward headed to the lane, together with Grosjean, a lap later to swap his option rubber for another set of primes.

McLaughlin pitted after 30 laps, releasing Newgarden who trailed the New Zealander by three seconds prior to his stop.

Penske fitted the alternate rubber to the Kiwi’s car, giving clear instruction not to push the out lap, which was further compromised by Lundqvist passing him at Turn 5.

Newgarden then dived into the lane, as did Power, the latter taking on a set of option tyres with the former remaining on the primary.

The pair emerged ahead of McLaughlin. Power tried to defend into Turn 3 but was unable to resist his team-mate, who already had tyre temperature, with Newgarden falling victim into Turn 5.

Like McLaughlin and Power, Palou stopped and swapped to the option tyre when he was in next time around, rejoining in a net seventh.

Herta inherited the lead once more ahead of Lundqvist, with McLaughlin third on the road, with a 2.1s advantage over Newgarden in fourth.

That was gradually eroded and the Indy 500 winner made his move for the lead down the front straight as they began Lap 36, breezing by McLaughlin as Herta and Lundqvist pitted.

McLaughlin appeared to be struggling for grip as he lost a second to both Newgarden and Power on Lap 35.

With 15 laps remaining, the final round of stops began, with Veekay and Rossi back in the lane.

Palou pulled the trigger next time by, feeding out in 13th having run eight seconds behind Power in third.

Penske called McLaughlin in from second on Lap 43, a late decision that pulled him out of second position and left him with free track once he rejoined.

Ahead, Newgarden was dealing with rookie Nolan Siegel, running wide at Turn 5 in the process. He pitted in response while Power remained on track.

A set of prime tyres were fitted for Newgarden, emerging well clear of McLaughlin to maintain position, the overcut proving especially powerful.

Power pulled in from the race lead at the end of Lap 44, swapping the option rubber for a new set of primary tyres.

The Australian rejoined in the effective race lead (Herta led but was yet to stop), over Newgarden and a similar advantage back to McLaughlin in third in a Penske one-two-three.

For a moment Power came under attack from Newgarden, defending once into Turn 1 as his tyres came up to temperature. Once they had, there was little Newgarden could do as Power held both track position and more push to pass time.

Herta remained out front with a 10-second advantage back to the trio of Penskes before eventually boxing with seven laps remaining.

He opted for another set of the option tyres for the run to the flag, feeding out in sixth and under attack from O’Ward.

That released Power into the lead from Newgarden, McLaughlin, Palou, Kirkwood, Herta, O’Ward, and Grosjean in the top eight.

Having seen off his team-mate’s initial challenge, Power went on to take the chequered flag, ending a 34-race win drought.

He led Newgarden by more than three seconds after 55 laps of racing with McLaughlin completing the Penske one-two-three.

Paulo was 15 seconds back from the race lead in fourth, 10 seconds ahead of Kirkwood, from Herta and O’Ward, who held off a late charge from Grosjean.

For Power it was his 42nd career IndyCar win, tying Michael Andretti for fourth on the series’ all-time winners list.

Results: Race, Road America

Race winner: 55 laps

Series points