IndyCar's Alex Palou will drive for Formula One team McLaren in opening practice at the U.S. Grand Prix on Friday, Oct. 21.
Palou will take the place of outgoing driver Daniel Ricciardo, who will then resume driving duties for the rest of the event.
Palou, who joined the McLaren racing programme earlier this year, has already privately tested a McLaren F1 car.
The opening session at Austin will also feature American driver Logan Sargeant, who will be in the Williams in place of Nicholas Latifi.
Sargeant remains in contention to race full-time for Williams next year.
The U.S. Grand Prix is a popular destination for teams to test young drivers. Friday's session will feature Robert Schwartzman driving for Ferrari, Antonio Giovinazzi for Haas and Theo Pourchaire for Alfa Romeo.
F1 rules mandate that teams must use young drivers who "may not have competed in more than two World Championship events" on two occasions in Friday practice throughout the year.
Mexican IndyCar driver Pato O'Ward, who is also part of the wider McLaren racing programme, will drive for McLaren at the opening session for the season-ending Abu Dhabi Grand Prix in November.