Toto Wolff says lumbering Valtteri Bottas with "pain in the ass" one-year deals could stop after the Finn highlighted how it had impacted his performances in 2019.

Although Bottas was the last man standing against Lewis Hamilton in this year's title race, the Briton won his fifth championship in six years at a canter.

After winning two of the first four races, Bottas slumped in Germany and Hungary as Hamilton surged clear – a period of the season that saw Bottas fielding regular questions about his Mercedes future.

Mercedes exercised the one-year option in Bottas' deal, but the Finn warned of falling into a similar situation next season.

"There was definitely uncertainty for 2020 at some point. Lots of rumours. I had no idea what was going to happen," Bottas said after leading Hamilton home at the United States GP.

Related Articles

Bottas back in Formula 1 title hunt after "overdue" win - Wolff

Bottas explains expletive response to critics

"I just had to wait. So, for sure, as an athlete, as a driver, it's not an ideal situation. You can't be completely with peace of mind and focus on the job and feel mentally free and in the right place. It's tricky.

"When that continues, you know, year after year, every single year of your career, at some point it's getting a pain in the ass – so it's definitely nice to get the contract signed. But, it's going to be the same story next year." And Wolff says he will keep the Finn's concerns in mind when plotting the future course for the Silver Arrows next year, when both Bottas and Hamilton will enter the final year of their existing deals.

"Apparently it has an influence on him so I will try to take that into account and do my job better," the Mercedes team boss said.

"In 2021, all the doors are open: none of our drivers have contracts with the team, so it will be a very interesting situation."