Sergio Perez has been withdrawn from the first practice session in India due to illness.
Sauber confirmed that the Mexican was not well enough to take part in practice but are hopeful that he will recover in time for Sunday's race.
A team statement read: "Due to the fact Sauber F1 Team race driver Sergio Perez is unwell, the Sauber F1 Team has decided to let its reserve driver Esteban Gutierrez jump into the car for the first free practice session ahead of the Indian Grand Prix on Friday. This should help Sergio's speedy recovery so he is able to drive for the remainder of the weekend."
Gutierrez is expected to replace Perez when the 22-year-old moves to McLaren at the end of the season.