Kurt Busch and Brad Keselowski have both vowed revenge on the other in the wake of their clashes during the Martinsville NASCAR Sprint Cup race.
The former Penske team-mates made contact during the first pitstops, with Busch's Stewart-Haas Chevrolet swiping Keselowski's Ford as he tried to get around a tangle between Keselowski and Kasey Kahne.
Keselowski felt Busch could have avoided hitting him, and when he rejoined 30 laps down after repairs, he made repeated deliberate contact with Busch on the straights.
Despite initially believing his car was too badly damaged to be competitive, Busch went on to charge from 25th to victory, winning his first race since the October 2011 Dover round.
Busch said he was stunned that Keselowski had felt the pit incident was worthy of revenge.
"I can't believe he overreacted and he's as upset as he is," he said.
"The #5 car was trying to pull into his box, Brad ran into the back of him, I steered right to go around Brad and then he clobbers our left-side door, and it's like, OK, accidents happen on pit road. It's congested. It wasn't that big a deal.
"I didn't think much of it, and then once we were back out running, he targeted us, he was aiming for us.
"He tried to flatten all four of my tyres. That's a no-fly zone. That's a punk-ass move and he will get what he gets back when I decide to give it back.
"If we would've got a flat tyre at that moment, we would have gone a couple laps down because it was a green-flag condition, and there would have been hell to pay."
Keselowski remained unrepentant after the race, and intimated that there would be further retaliation.
"If you're going to be aggressive, wreck yourself, don't wreck me," Keselowski said.
"I'll remember that when it's lap 50 and he needs a break, and he'll find his ass turned around in the wall. Just like he tore my car up.
"Once or twice when it happens, you start to go, 'Hey, it happens,' but when it happens repeatedly, you just realise who the person is who's at fault, and you just got to make sure you show them you're not going to take that, and I'm not going to take it."