In March he rode in the Paris-Nice. After stage two his teammate, Eddy Merckx, took the overall lead. Simpson moved into the lead the next day as part of a breakaway, missed by Merckx, which finished nearly twenty minutes ahead. Merckx thought Simpson double-crossed him, but Simpson was a passive member of the break. At the start of stage six, Simpson was in second place behind Bic-Hutchinson's Rolf Wolfshohl. Merckx drew clear as the race approached Mont Faron, with Simpson following. They stayed together until the finish in Hyères, with Simpson allowing Merckx to take first place. Simpson finished over a minute ahead of Wolfshohl, putting him in the race leader's white jersey. He held the lead in the next two stages to win the race. Three days later Simpson and Merckx both raced in Milan-San Remo. Simpson escaped early in a five-rider breakaway lasting about , before Merckx won in a bunch sprint with assistance from Simpson, who finished in seventieth placed. After of Paris-Roubaix, Simpson's bike was unridable and he retired from the race.