What happened: Ryō Hirakawa will make his Formula 1 debut Sunday at the Mexico City Grand Prix. The Japanese driver replaces Esteban Ocon at Haas for the race at Autódromo Hermanos Rodríguez.

Why it matters: The start marks a career milestone for the 24 Hours of Le Mans winner and Super GT champion. Haas turned to the reserve driver after altering its driver lineup ahead of the weekend sessions.

What to watch: Hirakawa takes the grid for Sunday's 71-lap grand prix in Mexico City.