The Richard Petty Motorsports driver was fighting for tenth place with team-mate Kasey Kahne on the final lap of the green-white-chequered restart, and as they ran along the back straight Kahne got a run on Allmendinger and tried to pass on the inside.
However Kahne was forced onto the grass as Allmendinger pulled to the left to block. He subsequently lost control of his #9 car and slid across the track, getting collected head-on by Greg Biffle and Mark Martin, before hitting hard against the outside wall.
"It was looking like we were going to finish decently," said Kahne. "I thought we had a better car than where we were going to end up, but still we would have been better than how it did end up. I don't know what AJ was doing there. I don't ever really talk to him much, but you can bet I will be talking to him this week."
Biffle, who took a hard hit and was one of at least ten drivers involved, was quick to blame Allmendinger as well. Hendrick Motorsports drivers Mark Martin and Jeff Gordon also suffered hard impacts, as did Marcos Ambrose who crashed against the inside barrier.
"I don't know what [Allmendinger's] deal is," said Biffle. "He totally caused that whole thing. If he is driving that blue car with the 43 on the side that put Kasey into the grass then yeah, it is on him. He ran him down on the grass.
"You can't run a guy down on the grass. You can't run your teammate down onto the grass. That is horrible. He could have backed out of that before he put him down like that."
Allmendinger accepted the blame for the incident, an incident that didn't cost him at all as he was able to cross the finish line in tenth place as the best Ford runner.
"I am not really sure what happened," said the Californian. "Kasey had such a run on me and I went to defend. By the time I defended he was in the grass. That is my bad. I feel bad about that, I really do. It is what it is though."
RPM's three cars were all part of the incident, as Elliott Sadler was also amongst those involved.
Kahne set for Hendrick move
