1991 Budweiser at The Glen

On the fifth lap of the race, a huge crash halted the event. McDuffie, driving the #70 L.C. Whitford-sponsored Pontiac Grand Prix for his own team, was racing Jimmy Means, driving the No. 52 Alka-Seltzer-sponsored Pontiac Grand Prix he owned, into the Loop turn. Both cars lost control and slid off the track, but McDuffie's situation proved more serious as he lost his left front wheel and suffered critical brake failure as a consequence. With no way to slow down, McDuffie careened across the grass and struck a tire barrier guarding a fence just outside the Loop with enough force to lift his car off the ground. Means slid into the tire barrier just as McDuffie's car was doing a 180-degree flip in mid-air, and the #70 came to a rest on its roof next to the #52 which Means was able to slow down enough to avoid a heavy impact.[2][3]

Means went over to the wrecked Pontiac to try to assist McDuffie, who had been killed instantly in the initial impact. Seeing how badly injured McDuffie was, Means began frantically waving for track safety officials to come to the scene.[5] The race was red-flagged for one hour and 48 minutes, first to extract McDuffie from his vehicle, and then to allow time for track workers to repair the guardrail in that location.[6] Later, as the race was restarting, NASCAR Winston Cup Media Director Chip Williams relayed to both the television audience and the national radio audience listening on MRN that McDuffie had died from his injuries sustained in the crash. On ESPN, Bob Jenkins then eulogized McDuffie before Benny Parsons spoke directly to McDuffie's widow, Ima Jean.[7] Coincidentally, Parsons had lost his wife two months earlier.[8] McDuffie was credited with a last-place finish of 40th.[9] A brief ceremony honoring McDuffie was held during the 1992 Coca-Cola 600 race held the following year.

This incident was the second serious accident at Turn 5 that year. During June's Camel Continental sports car race, Tommy Kendall crashed in the same area after losing control of his vehicle — he, like McDuffie, lost a wheel before crashing — and broke both of his legs. Coincidentally, Kendall was scheduled to take part in this particular race prior to his accident driving the No. 42 Mello Yello Pontiac for Felix Sabates in place of an injured Kyle Petty, but his injuries allowed Bobby Hillin, Jr. to take over the ride for the Budweiser at the Glen. (Hillin finished 18th.)

In the wake of both serious incidents, Watkins Glen International track officials decided to reconfigure the track and added a chicane called the Inner Loop to the entrance to Turn 5, which was renamed the Outer Loop. As of 2016 the track is laid out in such a manner that race organizers can use the chicane or bypass it in favor of the traditional setup, depending on the series.

When the race restarted, Terry Labonte maintained the lead. On lap 20, Labonte cut a left-rear tire and spun entering turn one, bringing out the caution to retrieve his tire. Ernie Irvan ran up front until he spun out of the lead in turn six on lap 48. Irvan re-entered the track in fifth place. A caution for rain came out on lap 59. The shower was brief and Ken Schrader emerged in the lead after pitting shortly before the caution. Schrader led until lap 68 when he broke a camshaft in turn five and coasted back to the pits. Later that lap, Kim Campbell spun in turn five, hitting the wall with the back of his Oldsmobile and bringing out the fifth and final caution of the day. The race came down to a three car battle between Irvan, Mark Martin, and Davey Allison for the victory. On the final lap, Martin attempted a pass for the lead entering turn one. Irvan blocked the attempt forcing Martin to slam on the brakes. This disrupted the balance of Martin's Thunderbird causing him to spin and Davey Allison to spin in avoidance. Irvan drove to a seven-second victory. Martin finished third while Allison had trouble restarting his car, finishing tenth. Coming out of the final turn, Bill Elliott and Hut Stricklin spun across the finish line, finishing seventh and eight respectively.