The Spanish wing-back's deal with Benfica includes a buy-back clause for former club United.
"I'm afraid Ruben Amorim will take him to Manchester United," Alvaro, a Benfica stalwart with over 200 appearances, told the Mirror, "It seems to me that he has the quality to be one of their first options, and looking at their squad, I believe with the new coaching staff, he could become an option again because the new coach knows him very well from what he saw at Benfica."
"When he debuted in the league, I saw a brilliant left-back in him. The way he positioned himself, how he touched the ball. For many, doubts are only now starting to dissipate.
"I feel today that many people have long been undermining a high-performance athlete with potential for high achievement.
"At Benfica, only the best should play, and he is undoubtedly the best. He was wronged within Benfica, but fortunately, he never gave up.
"That ability to react to adversity seems to be his strength," Alvaro continued. "Great players only succeed if they are mentally very strong, and that seems to be the case. If someone is weak, they can't play for Benfica, just as they can't play for Real Madrid, Manchester United, Bayern Munich, or PSG.
"If he were weak, he would have already been released from Benfica. He is one of those footballers we should fight to keep at the club because of their quality. I hope he has a lot of luck and continues to have a great season."
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