Even before the 39-year-old has taken charge of his first Red Devils game - which comes away to Ipswich Town on Sunday in the Premier League - the transfer rumour mill has inevitably started to swirl.
Having overseen the rise of several high-profile Sporting Lisbon stars, Amorim has been tipped to reunite with names such as Viktor Gyokeres, Geovany Quenda, Ousmane Diomande and Goncalo Inacio at Old Trafford.
Amorim has ruled out the possibility of raiding his former club in the January transfer window, although summer moves are not believed to be off the table, and the same goes for former Sporting stars as well.
According to the Daily Mail, Man United are running the rule over 22-year-old PSG left-back Mendes, who burst onto the scene under Amorim at Sporting before moving to the Ligue 1 champions on loan in 2021 and then permanently in 2022 for £31.6m.
Man United plotting swoop for 'fan favourite' Mendes
The Portugal international registered one goal and three assists in 47 matches for Sporting, playing all of those games as a teenager, and has since conjured up four goals and 13 assists from 93 appearances in a PSG shirt.
Mendes's rapid rise to stardom has also seen him become Portugal's first-choice left-back, and he supplied four assists in six Nations League group games between September and November as the Selecao advanced to the quarter-finals as group winners.
Even though the 22-year-old is said to be a fans' favourite at the Parc des Princes, where he has won three successive Ligue 1 titles, Mendes is yet to extend his contract beyond the summer of 2026.
PSG are expected to try to tie Mendes down to fresh terms as a matter of priority, but the French champions could be forced to consider a sale next year if talks with his camp fail to bear fruit.
Mendes has largely played as an out-and-out left-back at PSG, but he thrived as a wing-back in Amorim's 3-4-3 style, seemingly making him an ideal fit for his compatriot's project at Old Trafford.
Why are Man United targeting a move for Mendes?
In spite of the hundreds of millions that Erik ten Hag spent as Man United boss, Amorim has inherited a Man United squad in serious need of an overhaul, particularly on the left-hand side.
Diogo Dalot and Noussair Mazraoui have both been forced to play on their least preferred flank due to injuries to Tyrell Malacia and Luke Shaw, neither of whom have played a single minute in the current campaign.
The pair are on the verge of comebacks and may even be considered for places in the squad against Ipswich, but the report adds that Amorim could instead use Shaw as a left-sided centre-back rather than a wing-back.
If Malacia cannot prove his worth to Amorim, a new left-sided defender is likely to be sought in 2025, and the Red Devils are also said to be pursuing Bayern Munich's Alphonso Davies and Bournemouth's Milos Kerkez.
Real Madrid are thought to be confident of winning the race to sign Davies on a free transfer, though, while Liverpool are also running the rule over Kerkez's performances.