The Chelsea midfielder was a guest of Red Bull for the Spanish Grand Prix and was spotted in the team garage as he watched Formula One stars Max Verstappen and Sergio Perez in action.
He wasn't alone, though, with Blues' teammates Reece James and Ben Chillwell joining him in a potential last trip with his club colleagues.
Mount is one of the biggest talking points of the summer so far as a move away from Stamford Bridge gathers pace.
talkSPORT understands the England star has already agreed personal terms with the Red Devils.
Now, Man United have officially approached Chelsea to try and agree a fee.
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The midfielder has one year left on his contract in west London, meaning that the Blues are under pressure to cash in on the star or risk losing him for a cut-price fee.
Mount is keen to make the move to Old Trafford, which would see him leave the club he's been with since 2005.
Arsenal and Liverpool are also interested in the 24-year-old, however it's Erik ten Hag's side who are in the driving seat at present.
It's been suggested that Chelsea could demand a fee of around £80million for the star.
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