The 22-year-old joined Los Rojiblancos from Benfica in July 2019, and he has represented the La Liga outfit on 122 occasions in all competitions, contributing 29 goals and 18 assists in the process.
The Red Devils are yet to sign a new forward this summer amid speculation surrounding the future of Cristiano Ronaldo.
United boss Erik ten Hag is willing to let the Portuguese star leave the club, which would intensify the club’s search for attacking reinforcements.
Los Rojiblancos signed the Portugal international for £113m in 2019, but he has only scored 23 times in his 100 appearances across all competitions.
Although there is no prospect of the La Liga giants being able to recoup their money, a sale may occur with the Portuguese having started just 10 La Liga and Champions League games this term.
The England international has been strongly linked with a move to Old Trafford for some time, with the Red Devils thought to be keen to sign another right-back before the end of the month.
The 30-year-old, who is under contract with the La Liga champions until June 2023, has impressed since making the move to Atletico.
The 30-year-old is believed to be linked with a move to Manchester United in the current market.
A recent report suggested that the Red Devils are still working on a deal for the England international, who is valued at €40m by the Spanish champions.