Chris Buescher scored his first career Sprint Cup Series win in Monday’s rain-delayed Pennsylvania 400 when the race was called due to fog and an approaching storm on lap 138. Buescher battled back from a cut tire under green that put him in the back and opened up the need for pit strategy on a day that every team was racing the weather as hard as any competitor. As a green flag cycle of pit stops was nearing its end, Buescher and his Front Row Motorsports team chose to stay out as fog begin to build around the track hopeful for a stoppage. That stoppage came when spotters no longer could see turn 1. The race was then called after an hour and 20 minute red flag where the cars ended up being covered up on pit road because of weather in the area. Brad Keselowski who had been on an off-sequence pit strategy all afternoon, finished second. Regan Smith, who also had yet to pit, finished third for his first top five since 2012, and first since joining Tommy Baldwin Racing at the start of the season. Stewart-Haas Racing’s Kevin Harvick and Tony Stewart rounded out the top five. Joey Logano led a race high thirty-eight laps, but was forced to the garage for repairs on lap 106 after contact with Chase Elliott. Kyle Larson led thirty-seven laps and looked to have a car that would have competed for the win but fell back after contact with Austin Dillon while battling for the lead around the halfway mark. Larson would eventually work pit strategy to race back to finish sixth, while Dillon would finish thirteenth. The fast and furious racing to halfway and then to beat the impending weather produced nineteen lead changes among eleven drivers, and was slowed for caution seven times for thirty-one laps.