In 1989, Schumacher signed with Willi Weber's WTS Formula Three team. Funded by Weber, he competed in the German Formula 3 series, winning the title in 1990. He also won the Macau Grand Prix. At the end of 1990, along with his Formula 3 rivals Heinz-Harald Frentzen and Karl Wendlinger, he joined the Mercedes junior racing programme in the World Sports-Prototype Championship. This was unusual for a young driver: most of Schumacher's contemporaries would compete in Formula 3000 on the way to Formula One. However, Weber advised Schumacher that being exposed to professional press conferences and driving powerful cars in long distance races would help his career. In the 1990 World Sportscar Championship season, Schumacher won the season finale at the Autódromo Hermanos Rodríguez in a Sauber–Mercedes C11, and finished fifth in the drivers' championship despite only driving in three of the nine races. He continued with the team in the 1991 World Sportscar Championship season, winning again at the final race of the season at Autopolis in Japan with a Sauber–Mercedes-Benz C291, leading to a ninth-place finish in the drivers' championship. He also competed at Le Mans during that season, finishing 5th in a car shared with Karl Wendlinger and Fritz Kreutzpointner. In 1991, he competed in one race in the Japanese Formula 3000 Championship, finishing second.