"I just lost it in Turn 3," Johnson said. "The car was kind of loose. It just got out from underneath me. We definitely didn't need that."

The crash damaged the hood and front quarter panel of the No. 48 Chevrolet and team immediately unloaded the back-up car, but switching cars means Johnson must give up his pole position and start the race at the back of the field.

"The entire left side of the car is caved in," said Doug Duchardt, vice president of development for Hendrick Motorsports. "Aerodynamics here at Kansas is very important, so starting in the back [in the back-up car] is the best option in the Chase."

Johnson spent the final 30 minutes of Happy Hour getting laps in his back-up car. Johnson, the defending Nextel Cup champion, currently ranks third in the Chase, only four points behind leader Jeff Gordon.

The front of the field has seen change in the last 24 hours. Ryan Newman qualified in 2nd behind Johnson, but was forced to the back of the line because his roof was too low.