Sauber have confirmed Brazil's Gabriel Bortoleto will drive in 2025 alongside Nico Hulkenberg as the team prepares to transition to Audi for 2026.
The team announced on Wednesday Valtteri Bottas and Zhou Guanyu will leave at the end of the season.
Sao Paulo's Bortoleto joins from Formula 2 and leads the championship with two rounds remaining. The 20-year-old joined McLaren's driver programme in 2023.
The team said in a statement: "We are currently witnessing a generational shift in Formula 1, with young drivers immediately making an impact. By signing Gabriel Bortoleto, we have secured one of these top talents.
"His signing underscores Audi's long-term strategy and commitment to Formula 1."
Bortoleto said: "Joining a team that combines the rich motorsport history of Sauber and Audi is a true honour. Beyond simply being a member, I aim to grow with this ambitious project and reach the pinnacle of motorsport."
The Brazilian later spoke to reporters from Sauber's factory and joked about his relationship with Fernando Alonso who founded the A14 management company he is a part of.
"We always joke about it, to be honest, because before I was born he started racing in Formula One," the reigning F3 champion and F2 leader told reporters. "And now I'm getting there, I'm going to drive with him hopefully.
"He has been helping me obviously a lot in my journey teaching me a lot of stuff and supporting me ... and yeah, I think it will be very fun and I will have a good time with him."
Sauber boss Mattia Binotto was at Ferrari when Alonso raced for the Italian team between 2010-14 but said the Spaniard had stayed in the background when it came to talks about Bortoleto's future.
"We met in the paddock but he never influenced, he never tried really to come with me with convincing arguments," said the Italian. "I think what convinced me was Gabriel and nothing else. With Fernando I had once a chat but really very, very little."
Bottas leaves the team after three seasons. Last week he raised the possibility of returning to his former world championship team Mercedes as a reserve driver, where he won 10 races.
Sauber said in a statement: "Within the driver line-up, Valtteri has been a driving force, elevating both his teammate and the team with his unparalleled experience, enthusiasm, invaluable technical insights and fighting spirit.
"Joining as a rookie, Zhou formed a strong partnership with teammate, Valtteri Bottas, as the duo mixed experience and youthful enthusiasm. Zhou's learning curve was steep, but the Shanghai-born driver made quick progression and went on to establish himself as a reliable performer and an exciting driver with a knack for attacking.
"With three races still to run in the 2024 season, Zhou and the team will try their best to finish this journey in the most successful way possible: there's a job to do, and everyone in the team is determined to get it done in the best manner."