Vettel could jump ship to Mercedes in 2018

London - He will not replace Nico Rosberg in 2017, but the door to a future at Mercedes is a possibility for Fernando Alonso the year after.

That is the claim of Germany's Sport Bild, claiming that whoever Mercedes does sign to replace the retiring Rosberg will only get a one-year deal.

Vettel does have options

Still with his finger on the Formula 1 pulse is Gerhard Berger, who earlier this year negotiated the new two-year Mercedes deal that Rosberg is now giving up.

The former Ferrari and McLaren driver said: "Suddenly Ferrari is feeling the pressure. Sebastian will closely monitor their progress and take his time in renewing his contract.

READ: Bottas could lose Mercedes opportunity - Salo

"I'm sure deep down he wants the chance to go with Mercedes in 2018," Berger added.  "So Ferrari need to try to keep Vettel happy, so they don't lose him."

Other options

As Mercedes looks to replace Nico Rosberg, Finn Bottas - managed by team boss Toto Wolff but under firm contract to Williams - has been named as a top contender, along with Manor driver Pascal Wehrlein.

But Britain's Sun newspaper said Williams rejected "an initial approach" by Mercedes to slash in half the price of the Grove team's 2017 customer engine bill.

Williams, however, seems determined to hang onto the experienced Bottas.

READ: Wolff - 'Three names' on Mercedes F1 shortlist'

German F1 pundit Marc Surer told Speed Week: "Losing Bottas would be a disaster for Williams. Williams has compromised already to finance the team by signing Lance Stroll." 

When contacted by the Daily Mail, Williams refused to comment on the Bottas rumours.

Mercedes team boss Toto Wolff said: "We now have only three names on our list. If Nico had informed us earlier, it would be easier now. But perhaps we need to take a courageous decision. We do not want to create a big disturbance anywhere. Our plan had been to send Pascal to Sauber for one or two years to further develop. The (Sauber) team will be much better next year than it was in 2016."

"It is important that the second driver can help the team in the development of the car. That was Rosberg's great strength."