City may decide to let Sullivan stay in the States, either with the Philadelphia Union or their sister club New York City FC. Adu is, however, of the opinion that the hottest of prospects needs to familiarise himself with the demands of the European game as quickly as possible.
Adu - who, like Sullivan, made his MLS debut at the age of 14 - went on to say: “Well, if he's going to leave, if he's going to leave Philly and go to Manchester City, I think at that point it'll be better for him so that he gets that European football experience. I think it's better for him to get loaned to a European team, a team in Europe somewhere at that point.
“But don't rule out getting loaned to a team in MLS. The only reason that I would say that is because he just needs to get that European football experience. Because it's different. This will also be the first time that he's going to be away from the States or away from his family, away from home and whatnot. You have to adapt. You do. You have to adapt to the European lifestyle and the European culture and everything. And that is just as hard.
“Everything's different. There's so much pressure on the coaches over there. There's so much pressure on the front offices and whatnot. You have to win. Over there, you don't win, you get fired. You don't win, the team can get relegated. So there's a lot of different things going on at that point.
“Here in America, it's set up differently. There is no relegation at this point. You can come in last place and there's no, quote-unquote, consequences to that. You just get ready and you come back for the next season and try and win it again.
“So it's a little different dynamic. And the coaches are under so much pressure that it filters through the team. You can feel it. You can see the pressure on the coach’s face. You can feel it as a player. And that's what I think, he needs that experience. He needs to experience that to know that every single game counts.”