William Byron used a flurry of cautions to stretch his fuel over the final 140 laps to win Sunday's NASCAR Cup Series race at Iowa Speedway.

William Byron saves enough fuel to hold off late charges and completes the hat trick of winning at Iowa Speedway in all three national series.

More chaos strikes in the final stage as Chase Briscoe tags Tyler Reddick, sending him into Christopher Bell as the duo spins around.

Things keep getting wilder at Iowa Speedway as both Erik Jones and John Hunter Nemechek get involved in incidents during the ...

Cautions breed cautions as Carson Hocevar gets loose, sending Zane Smith into the SAFER barrier at Iowa Speedway.

See which Cup Series drivers are on the upswing, plus those who had a rough night in Sunday's race at Iowa Speedway.

Denny Hamlin spins early in final stage after contact with AJ Allmendinger during a four-wide battle after the restart at Iowa Speedway.

See the top highlights from Iowa Speedway, where countless cautions flew and a fuel-mileage gamble ended it. Related Videos ...

During a short sprint to end Stage 2, Brad Keselowski holds on while other cars find trouble during the restart at Iowa Speedway.

Brad Keselowski and Ryan Preece continued a hot stretch as they scored a pair of top fives in back-to-back weeks at Iowa.

After regaining the Regular Season Championship lead at Iowa, William Byron details what it's like sharing close battles with ...

During service under caution, Kyle Busch is forced to pit at an angle and shows his displeasure toward Alex Bowman out the window.