Seven racers in The Chase presented by Mobil 1 collided in the Lap 141 restart that began the final stage at World Wide Technology Raceway.
Bubba Wallace forced his way to the bottom of what became a four-wide wad through Turns 1 and 2 during the Enjoy Illinois 300 with fellow Chase contenders Chase Briscoe and Ryan Preece to his right with Josh Berry atop the four-wide situation.
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Room ran out as Wallace and Briscoe came together, sending both Toyotas for a spin. William Byron also contacted Wallace in the melee, incurring significant damage to his No. 24 Chevrolet. Byron entered the event last in the 16-driver Chase standings following an engine failure last weekend at Darlington Raceway.
Briscoe also contacted Preece while sliding sideways off Turn 2. Ryan Blaney and Denny Hamlin made contact as Hamlin swerved to avoid the calamity. Chase Elliott nearly missed the accident but got slight rear damage from Byron and Wallace.
All drivers were able to continue despite the crash, which necessitated the ninth caution of the day.
This story will be updated.