Lauda's previously good relationship with Ferrari was severely affected by his decision to withdraw from the Japanese Grand Prix, and he endured a difficult 1977 season, despite easily winning the championship through consistency rather than outright pace. Lauda disliked his new teammate, Reutemann, who had served as his replacement driver. Lauda was not comfortable with this move and felt he had been let down by Ferrari. "We never could stand each other, and instead of taking pressure off me, they put on even more by bringing Carlos Reutemann into the team." Having announced his decision to quit Ferrari at season's end, Lauda left earlier after he won the Drivers' Championship at the United States Grand Prix because of the team's decision to run the unknown Gilles Villeneuve in a third car at the Canadian Grand Prix.