Manchester United would've backed manager Louis van Gaal if he had decided to keep hold of Angel di Maria this season.
Yesterday, United accepted a €63 million offer from PSG for the Argentine, who is now in Qatar to undergo a medical with PSG officials.
A United source told Le 10 Sport: "I think the manager realized he had erred with Angel Di Maria and it was not going to work.
"Of course, Di Maria had a contract and we could force him to stay with Manchester United.
"But he felt that it was useless with a player who does not want to stay."
Di Maria will sign a four-year deal with PSG once he passes his medical later today.