Ferrari junior driver Antonio Giovinazzi will race alongside Kimi Raikkonen at Sauber in 2019, meaning Marcus Ericsson is out of a drive.
The Italian joins the team with backing from Ferrari and Sauber's title sponsor Alfa Romeo. The deal will see an all-new driver line-up for the Swiss team next year, with current driver Charles Leclerc replacing Raikkonen at Ferrari next year and Ericsson set to leave the team.
Giovinazzi raced for Sauber in 2017 when he replaced the injured Pascal Wehrlein at the Australian and Chinese Grands Prix, and has tested the 2018 car in Barcelona and at the Hungaroring this year.