Nico Rosberg would advise Mercedes to re-sign both of its drivers for 2019.
Both Lewis Hamilton and Valtteri Bottas are out of contract at the end of this season.
Rosberg told Turun Sanomat newspaper: "I would keep both. Absolutely!
"Lewis and Valtteri work very well together with a high level of performance."
The 2016 world champion thinks Mercedes should therefore resist the temptation to replace Bottas with Daniel Ricciardo.
"Only bad luck has prevented him (Bottas) from doing even better than he has," Rosberg said.