According to the Manchester Evening News, if Donnarumma joins Manchester United, the club can provide him with No. 1 or No. 99 jerseys.
Mannwan analyzed that Onana's frequent mistakes made him controversial, which triggered speculation from the outside world that Manchester United may consider introducing a new main goalkeeper. Manchester United has not set a budget for the new main goalkeeper, and Onana also learned that he will not be replaced, but French reports say that Manchester United is considering introducing Donaluma.
According to the team, Manchester United and Manchester City have expressed interest in introducing the Italian goalkeeper after Paris's contract renewal negotiations reached a deadlock. With Donnarumma's contract coming to its final year, Paris is willing to sell him this summer to recover some of the transfer fees. For Manchester United, bringing in Donnarumma is a huge expense when the team is in desperate need of strengthening the front line, but if they can bring him in at the right price, they can give him the jersey number he wants.
Donaluma is currently wearing the No. 1 jersey, which belongs to Baindel at Manchester United, but if a new goalkeeper joins, it may force Baindel to reconsider the future. If Donnarumma really joins, he will likely get the No. 1 jersey. A bolder and currently viable option is the No. 99 jersey, which Donnarumma has worn in Milan and briefly in Paris.
If Baindel was still on the team when Donnarumma joined, then his choice of the No. 99 jersey will likely make new teammates feel good about him. But there is still a lot to do before Donnarumma really joins Manchester United.