2024 could be Valtteri Bottas' last season in Formula 1, according to Finnish journalist Ismo Uusitupa.

When news broke that his former Mercedes teammate Lewis Hamilton would switch to Ferrari in 2025, Bottas teasingly posted on X a photo of himself sitting at a table with his phone in front of him.

He also hinted on social media that he recently visited Brackley - Mercedes' headquarters.

The 34-year-old now races for Sauber - to be called Stake F1 Team this year following Alfa Romeo's departure. But Uusitupa, writing in Ilta Sanomat newspaper, thinks Bottas could actually be left without a seat at all in 2025.

That is because 2025 Ferrari refugee Carlos Sainz is closely linked with a move to Audi - the VW-owned carmaker that is taking over Sauber for 2026.

"Bottas' chances to continue with Sauber are beginning to look slim," the F1 correspondent wrote.

"In theory, the other place (at Sauber-Audi) could be available. But if Sauber continues with the same system as several other lower level teams, Bottas will be left behind," Uusitupa explained.

"Sauber is now in the situation where Bottas is the hired driver and Zhou Guanyu is there with Chinese money. So if Sainz becomes the hired driver, the question is what kind of driver will the other one be?"

Bottas may therefore need to seek a new team for 2025, but Uusitupa said: "That's possible, but it may be difficult.

"In any case, Bottas has a big season ahead of him."