WEST ALLIS, Wisc. – In one of the wildest, wackiest races IndyCar has held in recent memory, it was Scott McLaughlin who weathered the attrition and terrible luck to pick up his third win of the year and hold off a hard-charging trio of Scott Dixon (2nd), Colton Herta (3rd) and Santino Ferrucci (4th).

But Sunday’s biggest race took place throughout the field, as the series’ two main, legitimate title contenders yo-yoed up and down the field with their own triumphs and bouts of bad luck.

Here’s how Palou managed to only lose 10 points to his championship lead and head to Nashville Superspeedway with a somewhat comfy cushion in his attempt to bring the series its first back-to-back champion in more than a decade:

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Alex Palou stalls on pace laps

Palou’s damage-control day began almost as poor as one could imagine, stalling during the pace laps not long before the 27-car field was set to take the green flag. Initially believed to be a hybrid issue, the AMR Safety Team pushed the No. 10 Honda back to Palou’s pit stall as the race began under caution for the stopped points leader. Palou would be released during a subsequent yellow – more on that in a minute – and quickly stall on the backstretch.

The safety team hooked the No. 10 Honda onto the back of a truck and wheeled it into the paddock. There, the CGR team replaced a 12-volt battery that controls the car’s ignition, according to NBC Sports pit reporter Dillon Welch. On Lap 29, Palau roared back out on-track sitting 25th with the 43-point championship lead he left Saturday’s race with nearly entirely evaporated.

Palou benefits from early caution, Newgarden wreck

Palou would’ve fallen several more laps down if not for another caution as the race attempted to go green for the second time. Race control opted to wave off that restart, claiming the back of the field had not properly packed up in the two-wide formation typical for race starts. That message, though, didn’t seem to make its way to the entire field, as 5th-place starter Linus Lundqvist sped up as polesitter Josef Newgarden and others ahead slowed, spinning Chip Ganassi Racing teammate Marcus Armstrong, who started 3rd, into the back of Newgarden.

Newgarden and Armstrong’s days ended there, with Lundqvist being handed an avoidable contact penalty and forced to perform a drive-thru. Sunday’s race finally was green flagged at the end of Lap 17.

Will Power takes race, series lead early

Power, who managed to survive the restart carnage after starting on the outside of Row 2, took over the race lead from his Team Penske teammate Scott McLaughlin on Lap 44 – and with that, the effective championship lead.

The race would go yellow for the third time on Lap 62 for a slowed David Malukas. Along with Nolan Siegel’s gearbox issue that ended his day, it meant Palou had already managed to climb up to 23rd to begin picking up additional points with every position he gained.

Much needed attrition for the defending series champ would come.

Alex Palou benefit from attrition

With Saturday’s race-winner Pato O’Ward also losing his gearbox on Lap 88 while running 5th, Palou would soon be handed an additional position, trailing Power in ‘points as they run’ by three nearing the race’s halfway point. Sting Ray Robb would bring out a caution on Lap 113 for spinning and stopping in Turn 2, and not long after the race restarted, Christian Rasmussen punted Graham Rahal to bring out another yellow and another car for Palou to eventually overtake.

Will Power spins, costing himself key positions

In perhaps the most shocking moment of the afternoon – which, of course, was saying something – Power spun on the ensuing restart all on his own, falling from 6th but managing to keep his car off the wall. For a moment, the temporary points leader pitted for new tires, but then came around under caution and pitted a second time for a new front wing and lost his spot on the lead lap. As the race returned to green on Lap 137, Power had fallen down to 13th.

Palou regains solid lead in championship

Over the race’s closing stretch, Lundqvist and Pietro Fittipaldi would also retire, handing Palou 19th to give him six more points than he would’ve earned had his team not managed to get him refired.

Power got back onto the lead lap with under 20 laps to go after Robb spun and crashed again, but would advance no higher than 9th and eventually finished 10th. What was one time a five-point lead for Power mid-race fell all the way back down to a 33-point gap for the Team Penske driver to make up in the season-finale in two weeks at Nashville Superspeedway.

This article originally appeared on Indianapolis Star: IndyCar: Alex Palou loses then regains championship lead in Milwaukee