Valterri Bottas has inched closer to replacing Nico Rosberg at Mercedes after reportedly visiting the German manufacturer's UK-based factory in Brackley before Christmas.
According to Motorsport.com, Bottas "tried out the cockpit of the 2017-spec Mercedes" car while also meeting the engineers he could be associated with next season.
Mercedes has been looking for a replacement to Rosberg since the 2016 world champion stunned the F1 community by announcing his retirement only a few days after winning the title in Abu Dhabi.
Although Bottas had a Williams contract for 2017, the 27-year-old quickly emerged as the front runner to land the seat.
The Grove-based outfit was initially reluctant to let Bottas go, but it has found a contingency plan in re-signing Felipe Massa, who had retired at the end of the 2016 campaign.
The Brazilian veteran will bring a wealth of experience to both Williams and new rookie team-mate Lance Stroll amid radical regulation changes.
The report adds that Mercedes did contemplate promoting Manor's Pascal Wehrlein but eventually ruled that its 22-year-old protégé was not ready to join a championship-caliber team yet. The former DTM champion has been tipped to find refuge at Sauber alongside Marcus Ericsson.
Mercedes has already said it will not make any official announcement until after the New Year.
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