Justin Allgaier won his first NASCAR Xfinity season championship Saturday night at Phoenix Raceway, making a stunning comeback after falling a lap down midway through the race.

Allgaier worked his way back through the field and passed Austin Hill and Cole Custer on an overtime restart with two laps remaining. Allgaier’s No. 7 Chevrolet took four tires during his pit stop before overtime, including two new ones on his right side, before shooting past Hill and Custer on the restart.

After Allgaier made the pass, a crash ensued, bringing out another caution, but the JR Motorsports driver survived the final restart to take home a long-awaited title.

“This is mind-blowing, it really is,” Allgaier said. “We tried to give it away every way we could.”

The 38-year-old Allgaier finished second in the race Riley Herbst, but it didn’t matter because he beat the other three championship finalists: Custer finished eighth, AJ Allmendinger was ninth, and Hill 10th.

It’s a big moment for Allgaier, who had won 25 Xfinity races in his career, but had never won a championship despite making the final four seven times over the past nine years. He finished in second in 2020 and 2023.

Allgaier had an eventful night, starting from the back of the field after switching to a backup car because of a crash during Friday’s practice. Regardless, he quickly shot up the leaderboard early in the race and it took him just 26 laps to enter the top 10.

But Allgaier got into trouble midway through the race when his back left tire started losing air following contact with Herbst. Allgaier lost a few positions, but was able to make it to the end of the second stage in 10th place.

His championship hopes looked as if they were dashed on the ensuing restart, when he received back-to-back penalties for an improper restart and then speeding on pit road. That dropped him to a lap behind the field, but he got back onto the lead lap after a well-timed caution when Anthony Alfredo crashed into the wall.

Given new life, Allgaier methodically worked his way back through the field before the crucial pass of Hill and Custer with two laps to go.

Allmendinger also started from the back of the field because he changed brakes after qualifying. He moved up to the middle of the pack fairly quickly, but struggled with his car for much of the night. Custer was in position to win back-to-back Xfinity titles for much of the night, but he couldn’t hang with Allgaier’s speedy car in the final laps.

Herbst also won the first two stages, which were both 45 laps.

Custer and Allmendinger are both moving up to the Cup Series next season.