Haas star Nico Hulkenberg announced his switch to the team in April, but the team have been taking their time in considering who will race alongside him for a lengthy period.
Whilst Sauber could opt for the experience of their current driver Valtteri Bottas, the outfit could also be tempted by the emerging talent of much younger racing stars.
Franco Colapinto was originally tipped for the drive at Audi, but has since been associated with the Red Bull family after Christian Horner was spotted leaving the Williams motorhome in Brazil, whispers of a potential buyout from his current team floating around the paddock.
However, Audi have another young star in their sights, with current Formula 2 championship leader Gabriel Bortoleto reportedly the recent favourite for the drive.
The Brazilian would become the first full-time driver from the country on the grid since Felipe Massa who left the sport in 2017.
Bortoleto was also in attendance at his home grand prix over the weekend, and discussed his chances of obtaining a drive in F1 for 2025.
"That is the question I ask myself on the daily. It depends a lot on my results," he said to Sky Germany at the Brazilian GP when asked when his home fans could expect to see him in a full-time F1 seat.
"In Formula 3, it went great. In Formula 2, it is going well as well. I think that if we continue like this and can secure the title, then I may have a chance in the future.
"Normally, if you win Formula 2, you somehow get into Formula 1. At the moment, I am focused on Formula 2 and I don't have my focus on Formula 1. That would not be the right approach."
Despite the 20-year-old's insistent remarks that he isn't focusing on a promotion to the pinnacle of motorsport, Bortoleto is signed under A14, Fernando Alonso's driver management company, with the F1 champion previously linked to negotiations with Sauber, potentially for the young star's benefit.