MotoGP star Valentino Rossi has completed a seat feat in a Mercedes Formula 1 car ahead of his eagerly-anticipated ride swap with Lewis Hamilton.

The respective multiple world champions are set to sample each other’s machinery on Monday (December 9) at Valencia’s Circuit Ricardo Tormo.

Rossi shared an image of him having a seat fit at Mercedes’ Brackley headquarters in a 2017-spec W08.

FEATURE: What we know about Rossi and Hamilton's F1-MotoGP ride swap.

The 40-year-old nine-time world champion captioned the picture: “I think me and Lewis Hamilton will have some fun soon” as he teased the seat-swap prior to expected official confirmation of the event.

Rossi has not driven F1 machinery in almost a decade, with his last outing coming in 2010 when driving a 2008-spec Ferrari F1 car at Barcelona’s Circuit de Barcelona Catalunya.

The Italian had been linked with a possible F1 switch throughout the 2000s after carrying out a number of test runs for the Scuderia.

The ride swap will act as Hamilton’s latest bike foray, after he tested a Yamaha R1m Superbike at Jerez in December last year.

The six-time world champion could not hide his excitement as he recently spoke about the upcoming event.

"I’m super excited about it,” he said at the United States Grand Prix last month.

“Just being on the same track at the same time as Valentino is going to be very, very surreal, and a real honour, because he’s such an icon in the sport, and he’s done so much. It’ll be cool to see him in my car as well.

”I’ve been riding bikes for the last couple of years. I’ve only done three days on them on the track, but they have been incredible, and I’m always watching MotoGP.

"There’s a small group of us in the team that love riding, and it’s something I’ve always wanted to do since I was young. It’s really hardcore."