F1: Wolff explains Bottas' one-year deal

Mercedes boss Toto Wolff has explained why Valtteri Bottas has only been handed an initial one-year deal to drive for the team.

Bottas was confirmed as Nico Rosberg's replacement on Monday, with the Finn moving from Williams despite having been under contract. The Mercedes contract is for one year with options for an extension, and Wolff says the team needed to keep its options open with a number of drivers out of contract at the end of 2017.

"We wouldn't have chosen Valtteri if we thought he wasn't good enough to continue with the team," Wolff told Oskari Saari and Alex Nieminen's Formulacast. "But as a matter of fact the market is very dynamic at the moment. Next year options open – young drivers, Sebastian [Vettel], Fernando [Alonso], Valtteri ... many of them - so it's about understanding that and Valtteri does.

"Equally we have great faith and confidence in him that he can stay with us for a long time, but now we have to see how the season goes."

Wolff accepts Bottas will need time to settle in at Mercedes before he can show his full potential and insists he is open to that taking longer than just pre-season, having only just been confirmed.

"We haven't even started testing yet. Valtteri is working every day, understanding the structure, meeting the people, learning the steering wheel and the technicalities of the Mercedes car. We have to give him time.

"I think he is going to spend a couple of days during testing seeing the difference between the Mercedes and the Williams and once the testing is finished we will then know whether he is ready to attack in Melbourne or where the missing dots are that we need to link.

"So I have no doubt that he has the capability of being very successful, but I don't want to make any predictions about when he is going to challenge Lewis. Lewis has been with us for a couple of years, he is a three-time world champion and as much as Valtteri is going to create pressure for himself I don't think it's necessary to do that at the beginning of January."