Memphis Depay completed a transfer to Lyon in January 2017 and Manchester United manager Jose Mourinho explained his buy-back clause at the time.
"Because potentially he's a very good player," Mourinho responded. "I think when Mr Van Gaal decided to buy him he did well, he knew him very well from the national team, he was very young when at the World Cup he had flashes of top quality.
"He was playing well in Holland, we know the Dutch league is not the same but he was showing very good things. So I think Mr Van Gaal and Manchester United did very well to buy him.
"He didn't succeed in his 18 months but he's very young so I think it's important for the club to complete control of this talent and we all wish he plays very, very well at Lyon and why not to come back because everyone here likes him."