Also in 1971, the "Stichting Autoraces Nederland" (Foundation for Car races in the Netherlands) hired a Surtees TS7 for him to make his F1 debut in his home GP where he finished a creditable eighth in a very wet GP. The following year Van Lennep won the 1972 Rothmans European Formula 5000 Championship driving a Surtees TS11 and a McLaren M18. He also drove twice for the Williams GP team, earning his first World Championship point with sixth place in the 1973 Dutch Grand Prix. With Ensign, he scored a second point in the 1975 German Grand Prix, making him the fifth most successful Dutch Formula One driver behind Max Verstappen, Jos Verstappen, Carel Godin de Beaufort and Christijan Albers.