Mercedes boss Toto Wolff has given Valtteri Bottas a target to meet if the Finn is to remain with the German squad beyond 2019.

Bottas enjoyed a good start to his campaign last year, his consistency helping him establish himself early on as a contender for the title.

But misfortune and under-performance saw the Mercedes driver progressively distanced over the summer by team mate Lewis Hamilton, to the point where Bottas was relegated to a support role at the Silver Arrows outfit.

While recognizing his driver's run of bad luck in 2018, Wolff insists that Bottas must step up his performance this year, especially with Mercedes reserve driver Esteban Ocon waiting in the wings.

"Valtteri knows exactly where he needs to be next year," said Wolff. "He needs to have all the bad luck gone and perform on a level with Lewis.

"That is what is needed for the 2020 year. He knows very well that, and he has that in him."

Racing on a par with his five-time world champion team mate will be a tall order for Bottas with Hamilton expecting to also raise his game and sustain his momentum.

But Wolff is convinced the Finn is capable of stepping up to the next level and giving Hamilton a proper run for his money.

"Beating a five-time world champion at the peak of his activity, peak of his performance, is going to be very difficult and Valtteri knows that. But I think that he has it in him.

"I think that he can win – he has proven it this year on a few occasions, but he had bad luck or was in a position where he could not win.

"I think if that turns into a positive momentum that is actually driving for the championship, I think that Valtteri can win the championship."

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