The day was Feb. 18, 1979.
Donnie Allison was battling Cale Yarborough for position on the final lap of the Daytona 500, with all other competitors a half-lap behind. Yarborough was drafting Allison tightly and looking to slingshot. Allison refused to give up position, and both drivers ended up spinning out, allowing Richard Petty to shock everybody and take the checkered flag.
This was the first ever 500-mile racing event that was featured from start to finish on live television (CBS). Fans certainly got a show. Allison, his brother Bobbie, and Yarborough engaged in a fist fight immediately following the race—a moment that would live on in infamy.