Just after the restart to begin the final stage, Ryan Blaney slid up the track and stacked up the midfield exiting Turn 4.
On the frontstretch, the field went three-wide and Kurt Busch got into Aric Almirola, who in turn hooked Kyle Busch into his teammate Martin Truex Jr.
From that point on, the wreck was on. Busch slid through the grass while Truex slammed the outside wall before getting hit by oncoming traffic.
Among those involved were William Byron, Ricky Stenhouse Jr., Ryan Preece, Matt Kenseth, Chris Buescher, Clint Bowyer, Bubba Wallace and Kentucky winner Cole Custer.
«It’s always one of the most humbling sports you can be a part of. Winning last night and part of a wreck this week,» said Custer. «I was as hard on the brakes as I could and then the No. 19 (Truex) I think came down from hitting the wall and just one of those things, you couldn’t really go anywhere.»
NASCAR immediately displayed the red flag to clean the track of debris, which lasted for 11 minutes and 29 seconds.