lapsing on to five cylinders, finishing sixth overall. Michael and Mario join Busby Racing for 1989 Daytona 24 Hours, only for their 962 to retire with brakes problems. The 1988 CART season was a lean year for Michael. He remained with Kraco and won only a single race, the Marlboro Challenge, for which no championship points were awarded. For the 1989 season, Andretti signed with Newman/Haas Racing, partnering him with his father. He won two races that season, Molson Indy Toronto and the Marlboro 500 at the Michigan International Speedway, placing third in points. For 1990, Al Unser Jr. would become champion, Andretti was his nearest competitor, winning five races and four poles. In the second-to-last race of the season at Nazareth, Unser crashed out, giving Andretti a huge opportunity to close the gap. Andretti managed only a sixth-place finish, and could not capitalize on Unser's misfortune. Unser left Nazareth with a 27-point lead, enough to clinch the championship. Andretti would finish runner-up once again. For the 1991 24 Hours of Daytona, Mario was joined by both Michael and his Mario's younger son, Jeff Andretti. Piloting a Jochen Dauer Racing entered Porsche 962, they were classified fifth overall, despite not finishing the race. Andretti was the drivers' champion of the 1991 CART PPG Indy Car World Series. He won a total eight of 17 races, eight poles and led more than half of the laps during the season, but Rahal still took the championship battle down to the final race of the season. Andretti's season started slowly, recording DNFs in the opening two events, then the heartbreaking second place at the Indy 500. He recovered from this, winning four of the last five races of the season and with Rahal retiring during the title decider at Laguna Seca, he cruised to the title. The day before, he won the non-championship, Marlboro Challenge for a second time. Remaining with Newman/Haas for 1992, Michael's season started slowly, but then wins three races out of four mid-season. Despite taking two more wins later in the year, including the season finale at Laguna Seca, Rahal beat him again to the title by just four points. He would leave for F1 at the end of the year, with his seat going to the reigning Formula One World Champion, Nigel Mansell, who would win the 1993 CART title in his rookie season. For four seasons between