"That shows just how fast things can change out there," said Busch, who played catch-up all race long as his Steve Addington-led team started back in the 38th position. "We definitely did not need those late cautions. With 20 to go, it looked like we were going to come out of here with a solid top-10 finish, but it was not to be. We fought the car being too loose or too tight most of the day. Just a half-pound air pressure change would make the car go from sideways loose to really tight.
"We still looked to be a threat for a top-10 until we had the run-in with the 6 car (David Ragan)," said Busch. "He just washed right up the track and pinned is into the wall. The left-front tire blew and we had to pit for repairs. We were running wounded out there on the last restart, but still made it back up from 30th to finish 21st. It could have been a really solid day here for the Miller Lite Dodge, but I guess it just wasn't meant to be. Hopefully, we can bounce back next week at Charlotte."
Busch started 38th Sunday and fought handling issues from the very beginning of the race. Addington and crew used air pressure, wedge and track bar adjustments throughout the day. Busch was up to 14th on a Lap 142 restart after the fifth caution period of the day. The handling characteristics of Busch's Dodge went from being extremely tight to "pushing like a dump truck" tight with just a half-pound air pressure adjustment.
Busch was turning in the fastest lap times of all the drivers on Lap 180 as he was battling Matt Kenseth for the ninth spot when the eighth caution flag of the race flew, this one for debris on Lap 182. Busch hit pit road under the yellow for four tires and fuel, with the only adjustment being a tenth of a pound of air pressure put into the left-rear tire.
Busch was 11th on the Lap 188 restart. He slid as far back as 16th and began moving back toward the front. He was back up to 14th on Lap 193 when Ragan drifted from the lowest lane of the track straight up and into Busch, pinning him into the outside wall. The two cars came off the wall almost attached and it wasn't until they were half-way down the straightway that they separated. The damage done to Busch left-front fender blew out the tire and forced Busch to pit road immediately.
The team made three trips to their pits for repairs and fresh tires under the yellow. Busch fell to the rear of the field and the 29th spot for the Lap 199 restart and was able to somehow steer his wrecked car back up to finish 21st.
Up front it was Tony Stewart holding off Clint Bowyer for the win. Jimmie Johnson finished third, with Kasey Kahne fourth and Ryan Newman fifth. Kevin Harvick, Denny Hamlin, Jeff Gordon and David Reutimann rounded out the top-10 finishers.
Several other Chase drivers faced problems here today, with mechanical woes seeing Greg Biffle finish 41st, Kyle Busch 35th, Carl Edwards 34th and Kenseth 30th.
Sam Hornish Jr. led the three-car Penske Racing contingent on Sunday with a 15th-place finish. Brad Keselowski finished 26th.
With six races remaining in the Chase, Johnson (5,673 points) holds the lead by 36 points over Hamlin (5,637 points). Harvick (5,619) is third, with Gordon (5,588) fourth and Stewart (5,566) fifth. Kurt Busch is sixth with 5,533 points, with Edwards (5,511) seventh, Jeff Burton (5,496) eighth, Kyle Busch (5,486) ninth and Biffle (5,458) 10th. Kenseth (5,432) is 11th and Bowyer (5,426) is 12th.
The Cup Series tour now heads back to Charlotte Motor Speedway next week for the Bank of America 500. Busch and his Miller Lite Dodge Team will be trying for a piece of history. He will be attempting to become the first driver ever to win all three Cup races in the same year at Charlotte.