Jose Mourinho is short of a winger after missing out on Inter Milan star Ivan Perisic this summer.
If reports are to be believed, Gunners boss Arsene Wenger came close to securing the 21-year-old Monaco forward's services with a massive £92m bid on transfer deadline day - unable to land what would have been his third major summer signing, Wenger claims Arsenal will try again for Lemar in January or next summer.
And, according to the Mirror, the Portuguese chief has identified Lemar as the flawless player to fill the void.
According to the same story, Lemar's representatives are aware that the Red Devils are interested in signing the Monaco player.
Unfortunately for Gunners fans, Lemar did not join the list of big money players to move on from the Ligue 1 side in recent seasons and now, club vice-president Vadim Vasilyev has revealed why.
He was subbed at half-time as Monaco were thumped 4-0 by Nice on Saturday night with Paris Saint-Germain look set to run away with the French title this term.
Manchester United will start their Champions League campaign with a home clash against Basel at Old Trafford on Wednesday night.
Any move for the France global will likely top the £89m club-record fee shelled out for Paul Pogba previous year.
Arsenal will allegedly return for Lemar next year having missed out last month, but the France global may be spoilt for choice, as United allegedly prepare a move to land him as Mourinho's new winger.