Ambrose was fined $25,000 and placed on probation through May 28. Mears was fined $15,000 and received the same probation.
NASCAR said in a statement both drivers were penalized for actions detrimental to stock car racing, and received a "Behavioral Penalty" because they were "involved in an altercation in the garage area after the race."
The two had been racing for a top-20 finish Saturday night when something occurred on the track to anger Mears. He confronted Ambrose in the garage area after the race, and shoved the Australian as Ambrose seemed to be walking away.
Ambrose responded with a right hook to Mears' eye that drew blood. He has not commented on the incident, but Richard Petty Motorsports issued a statement saying Ambrose would not appeal the penalty.
"Marcos Ambrose accepts the penalties levied by NASCAR after his actions at Richmond International Raceway," the statement said.
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