The German was once the sport's dominant force, clinching four successive drivers' titles from 2010-2013 whilst at Red Bull.
Much was expected of Vettel when he made the switch to Ferrari in 2015, but things didn't go to plan before eventually moving on to Aston Martin in 2021 for what was supposedly his final season in the sport.
Rosberg makes case for Audi deal
In recent months, however, the 53-time race winner has been tentatively linked with a shock return, with his former boss at Red Bull, Helmut Marko, revealing last month that Vettel wanted to make a comeback.
It's not the first time his name has popped up this season, with Mercedes previously touted as a potential destination following Lewis Hamilton's announcement that he would be joining Ferrari in 2025.
Sauber - soon to become Audi - have also emerged as realistic contenders, with the team still searching for a driver to line up alongside Nico Hulkenberg.
Now, 2016 world champion Nico Rosberg has tipped his compatriot to earn that vacant seat.
Speaking to Sky Germany at the Italian Grand Prix, the former Mercedes star said: "I would take Sebastian Vettel for Audi - Sebastian has to go in. Why not?
"With Nico Hulkenberg, they know exactly what they would have there: a great driver who is really driving great right at the moment and Sebastian would come back.
"You would have to make sure that he drives enough kilometres somewhere, and that would be a great thing, I think."