Quenda, 17, has been a vital player for Sporting this season, making 15 appearances in all competitions, scoring twice and registering one assist, and he is regarded as one of the best young talents in world football.
Manchester City and Arsenal have also been credited with an interest, but it is believed that Man United are in a strong position to sign Quenda, who could follow in Cristiano Ronaldo's footsteps by moving to Old Trafford from Sporting.
According to A Bola, Man United had a scout in attendance to watch Quenda in action against Famalicao in Portugal's top flight on October 26, and he scored in Sporting's 3-0 success.
The goal saw him become Sporting's youngest-ever scorer in the league at the age of 17 years, five months and 27 days old.
Man United 'determined to win the race' for Quenda
The youngster has broken into the Sporting first team this season, and he signed a contract extension with the Green and Whites last month, with his release clause increasing to €100m (£83.5m).
However, there is a feeling that the Portuguese giants will struggle to keep hold of him beyond next summer, with a number of major clubs expressing an interest in his services.
Quenda had an impressive record of nine goals and seven assists in 24 appearances for Sporting Under-23s before rising to the senior side, and he primarily operates as a right-sided wing-back.
A recent report claimed that Man United view him as a 'potential future star of world football' and are determined to beat a number of clubs to his signature.
Could Amorim situation give Man United the edge?
Man United are seemingly close to appointing Sporting's Ruben Amorim as their new head coach, with the Portuguese expected to soon be confirmed as Erik ten Hag's replacement.
It is understood that personal terms have already been agreed, but Man United are still locked in talks with Sporting over his buy-out fee, as they could be forced to pay more than the €10m (£8.3m) release clause in order to secure his services immediately.
Ruud van Nistelrooy will lead the team into Wednesday's EFL Cup clash with Leicester City and will also seemingly be in charge of the clash with Chelsea in the Premier League this weekend, unless there is a breakthrough over the next 24 hours.
Amorim's likely arrival at Old Trafford could therefore give Man United a huge advantage in the race for Quenda, as the 39-year-old handed the teenager his big chance in professional football.