Mercedes look set to keep Valtteri Bottas on board for 2018.
Since replacing Nico Rosberg, the Finn has won two races and is just 15 points behind his triple world champion teammate Lewis Hamilton.
However, boss Toto Wolff said that another factor in play is the driver market for 2019, when big names including Daniel Ricciardo and Max Verstappen may be available and Hamilton's current deal expires.
Some insiders therefore believe Mercedes that will ink a new one-year contract with Bottas to fill the gap for 2018.
"The market will be quite interesting in 2019 so you have to plan ahead," boss Wolff told Bild.
The 2017 championship continues on Sunday with the British Grand Prix.
