Sauber has signed Mexican teen Esteban Gutierrez as its test and reserve driver.
The new GP3 champion has attended a number of Grands Prix this year in an observational role with the Swiss based team.
He will now be the reserve driver at all races in 2011, and will test the C29 after the season finale in Abu Dhabi.
"We are confident he will continue to develop strongly," said team boss Peter Sauber.
19-year-old Gutierrez added: "Formula one is my ambition, and I'm really grateful to Peter Sauber for his confidence in me and my ability."