Amorim is widely expected to implement a 3-4-3 formation at Man United, with the Portuguese having so much success with that system during his time in charge of Sporting Lisbon.
Porro played under Amorim at Sporting, with the Spain international thriving down the right, and according to AS, Pedro's representative believes that Man United will now make an attempt to sign the defender.
The report claims that Amorim has an 'excellent relationship' with Porro, and the Red Devils could potentially move ahead of Real Madrid to the top of the queue for his signature.
Real Madrid are in the market for a new right-back, and it is believed that Porro is their number one alternative to Trent Alexander-Arnold, should the Englishman sign a new contract at Anfield.
Porro's camp 'expecting interest from Man United'
Tottenham allegedly value Porro at a minimum of €70m (£58m), which makes a deal difficult, but the Spaniard could potentially attempt to force a switch to Old Trafford next summer.
The 25-year-old has scored once and provided two assists in 13 appearances for Tottenham during the 2024-25 campaign, while he has a record of eight goals and 12 assists in 67 matches for the North London club in total.
Porro scored 12 goals and registered 20 assists in 98 matches for Sporting, meanwhile, and it is believed that Amorim could target him as his new right-sided wing-back at Man United.
Diogo Dalot and Noussair Mazraoui are options in that area of the field, but Amorim allegedly has reservations over their suitability for the role, with Porro viewed as more productive in the final third of the field.
Man United are 'also in the market for a left-sided wing-back'
Two wing-backs could potentially arrive at Man United next year, with the 20-time English champions also said to be determined to bring in a new left-sided player to fit Amorim's system.
Luke Shaw and Tyrell Malacia are both now back to full fitness, but concerns remain over the duo, with the former struggling with multiple muscular problems, while the latter has not played for the first team in 18 months.
Bayern Munich's Alphonso Davies is thought to be Man United's leading target in that area of the field, but Bournemouth's Milos Kerkez and Wolverhampton Wanderers' Rayan Ait-Nouri are also allegedly admired.
Amorim has stopped short of confirming that he will implement a 3-4-3 system at Man United, but that is widely expected to be the case, and the Portuguese is currently preparing his side for Sunday's Premier League clash against Ipswich Town.