Riding near the wall at the bumpy 1.5-mile oval, Larson passed Harvick with about 60 laps remaining in the 300-mile race. Brandon Jones moved into the top spot when he stayed on the track while the leaders went in for a pit stop, but the caution he needed never materialized and Larson pulled away when Jones finally went into pit road on a really hot day all over the Midwest.
Larson also won the pole, but the NASCAR Cup Series regular was sent to the back of the field because of an unapproved tire change after qualifying. It was his second win in three starts on the Xfinity Series this season, joining his victory at Las Vegas in March.
The temperature was in the 90s for most of the day, and it soared well into triple-digits inside the cars. Ice bags were almost as popular as new tires at each pit stop. Harvick asked his crew for a smaller, sandwich-sized bag when he was unable to fit a large bag in his suit, and he splashed cold water on his face at one point.
“Water, ice and a towel at the finish line,” Larson requested after his 10th career Xfinity victory.
The 25-year-old Larson felt his No. 42 ENEOS Chevrolet was in bad shape after practice on Friday, and he praised his team for its extensive work overnight. He moved in front for the first time about 70 laps into the 200-lap race.
Tyler Reddick started in front after Larson’s tire problem, and then won the first stage. But he had a slow pit stop and was penalized for speeding into pit road before he was knocked out of contention by a wreck.
Justin Allgaier, an Illinois native who won the Chicagoland Xfinity Series race last year, finished seventh. He was trying for his second straight victory after winning at Iowa on June 17.