Formula One will have a full-time Brazilian driver for the first time since 2017 after Sauber announced 20-year-old Gabriel Bortoleto to complete the future Audi team's line-up for 2025 and 2026.
The Swiss-based team had earlier announced the departure of Finland's Valtteri Bottas and Zhou Guanyu, China's first F1 driver, at the end of the season in December.
Sauber, who will become the Audi factory team in 2026, already announced 37-year-old German driver Nico Hulkenberg - currently at Haas - in April.
Bortoleto is currently leading the F2 championship, after winning F3 last year, and is part of the McLaren driver development programme as well as two-times champion Fernando Alonso's A14 driver management company.
Formula One leaders McLaren confirmed separately he would be released at the end of the year.
"Joining a team that combines the rich motorsport history of Sauber and Audi is a true honour," said Bortoleto, who will be his country's first regular F1 racer since Felipe Massa.
"I'm incredibly grateful for the opportunity given to me by the team and for the chance to work alongside an experienced driver like Nico."
Sauber, who entered Formula One in 1993 and finished runners-up under BMW ownership in 2007, are last in the constructors' standings and the only team yet to score this season with three rounds remaining.
They have big plans for the future, though, and appointed former Ferrari team boss Mattia Binotto in a managerial overhaul in July.
"Gabriel has already demonstrated in the junior categories that he has what it takes to be a winning driver. We are very pleased that he will become a team member of Sauber and Audi," said the Italian.
"Together with Gabriel, we are on a journey towards success, and we will evolve into a unified force to shape a new era for Audi in motorsport.
"Nico and Gabriel represent the ideal combination of experience and youth, positioning us strongly for the future."
Bortoleto is the latest in a line of exciting young talent coming into Formula One.
Mercedes have signed 18-year-old Italian Kimi Antonelli to replace seven-times world champion Lewis Hamilton, departing for Ferrari, while 19-year-old Briton and Ferrari protege Oliver Bearman takes Hulkenberg's place at Haas.
Renault-owned Alpine have also signed Australian Jack Doohan, 21, the son of motorcycle great Mick, while Williams have Argentinean Franco Colapinto, also 21, racing for them this season after dropping American Logan Sargeant.
Red Bull's RB have also brought in Liam Lawson, 22, as replacement for Australian Daniel Ricciardo with the Kiwi favourite to retain the seat.
"We are currently witnessing a generational shift in Formula One, with young drivers immediately making an impact," said Sauber Motorsport chairman Gernot Dollner.
"By signing Gabriel Bortoleto, we have secured one of these top talents. His signing underscores Audi's long-term strategy and commitment to Formula One."
Sauber said they held "open and constructive discussions" with Bottas and Zhou before a mutual decision to part.
"After all the good and in-depth discussions we had in the past weeks, we realised that the conditions to grow this project together were not met," said Bottas, 35 and a 10 times grand prix winner with Mercedes.
"Though it's time to move on, I'll always carry a piece of this team with me, and I look forward to seeing what the future holds for us both."
- Reuters
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