The 33-year-old was heavily linked with a move to Man United throughout the summer transfer window, but it ultimately didn’t materialise.
Several reports had suggested that Martinez spent transfer deadline at Aston Villa’s training ground waiting for a call from United that never came.
Ruben Amorim’s side did manage to sign a new goalkeeper, spending a reported £21.5 million on Senne Lammens from Royal Antwerp.
Martinez’s brother, Alejandro, has since come out to clear up exactly why the move to Old Trafford didn’t happen.
Speaking to DSports Radio, he said: “I was told that Emi gave a lot as a professional and as a person, they love him, and you could see that on the pitch.
“He is well-liked, and the directors didn’t want to sell him because he is the key player in the team, and another team wanted him. It was that commercial dispute.
“These are decisions made by club officials. It didn’t happen, but it’s like everything else in business.
“The sporting side of things was left out of it, and everything is fine. Emi never had an argument with Unai; it was all within the management’s control, and the clubs couldn’t agree.
“At Aston Villa, he’s the Diego of Napoli. He gave a lot at Villa, like Kun did at City, like Leo did at Barca. They’re legendary players, and it’s going to be hard to surpass what he did at Aston Villa.”