1973 Winston Western 500: Donohue Dominates By: MRN Staff on December 23, 2014 | 12:45 P.M. EST Donohue had his Penske-owned AMC Matador in the lead for 138 of the 191 laps. It took nearly five hours to run the race, with Donohue the only driver to complete every lap. (Photo: ISC Archives) Share on facebook Share on twitter Share on print More Sharing Services Print Email Share In January 1973, driver Mark Donohue and car owner Roger Penske kicked off NASCAR’s 25th season with a command performance in the Winston Western 500 at Riverside International Raceway. Donohue humbled his 39 rivals and tamed the 2.62-mile Southern California road course, lapping the field for his first Cup Series win in just his fifth career start. Donohue had his Penske-owned AMC Matador in the lead for 138 of the 191 laps. It took nearly five hours to run the race, with Donohue the only driver to complete every lap. His racecar was equipped with four-wheel disc brakes. "It made the difference," Donohue said. "I could carry the car deeper in the corners and that's what it takes on a road course." After the race, Penske had high praise for his driver. "One of the reasons Mark is so good is that he can evaluate what we're doing on the drawing board," Penske said. "You might call him a built-in reliability factor. He's the most consistent driver in the business. He's not driving 102 percent - over his head. It's more like 98 percent. There's always something in reserve." Future Hall of Famer Bobby Allison finished second with Ray Elder, Bobby Unser and Jimmy Insolo completing the top five. Pole sitter David Pearson failed to lead a lap and completed less than half the race distance before retiring with clutch failure. He finished 22nd. Benny Parsons placed 14th to open what turned out to be a championship season. Despite winning just one race – in July at Bristol, Parsons had 20 other top 10s among his 28 starts. He topped runner-up Cale Yarborough by 67 points. Riverside would be the site of the season-opening race until 1982, when Daytona International Speedway took its place at the top of the schedule – where it remains today. Riverside was dropped from the NASCAR slate following the 1988 season.