MEXICO CITY (AP) — Haas is giving Ryo Hirakawa a Formula 1 race debut in Mexico on Sunday after announcing abruptly Saturday that he would replace veteran Esteban Ocon.

In a rare change part-way through an F1 weekend, the Japanese driver will step in for Ocon for third practice and qualifying on Saturday and the race, as teammate to Oliver Bearman.

Haas did not explain the change, commenting only that Ocon was not being replaced due to illness. Other drivers including championship leader Kimi Antonelli have been unwell this week.

Hirakawa, a former Le Mans 24-hour race winner for Toyota, had already driven first practice for Haas on Friday in Ocon's car.

At the time, it appeared Haas was simply fulfilling F1 requirements to give non-regular drivers track time in a set number of practice sessions each year. Hirakawa was 15th-fastest before Ocon got back in the car and went 13th-fastest in second practice.

Haas left open who would race next week in Brazil, the first of four more races scheduled after this week in Mexico.

Ocon is already due to leave Haas at the end of the season after two years and has indicated he wants to stay in F1, even as another team's reserve. The 30-year-old French driver took his only F1 win in 2021.

Haas this month signed Formula 2 leader Rafael Câmara for next season.

Ocon was previously released before the end of the season in 2024, when Alpine entered Jack Doohan in his place for the season-ending Abu Dhabi Grand Prix as he prepared to leave for Haas.