The two-time Xfinity Series champion from Corning, California, led a race-high 38 of 86 over-scheduled laps before fending off Chastain in overtime to grab his second Cup Series career victory.
The 40-year-old Allmendinger from Los Gatos, California, led all but 20 of 62-scheduled laps en route to his third Xfinity Series victory of 2022 at the Brickyard.
The 2016 Indianapolis 500 champion dominated the second half of the Gallagher Grand Prix to snap a 49-year winless drought and score his eighth IndyCar career victory.
The 37-year-old Enfinger from Fairhope, Alabama, overtook Zane Smith during an overtime attempt to snap a one-year winless drougth and become the first Playoff competitor to transfer from the Round of 10 to 8.
The 2020 Cup Series champion was awarded his fourth victory of 2022 at the Tricky Triangle following the post-race disqualifications of race winner Denny Hamlin and runner-up Kyle Busch.
