Paul Ince urged Jadon Sancho to think carefully about choosing to join Manchester United in the summer.
The Red Devils have been linked with a move for the Borussia Dortmund star at the end of the season.
Sancho has a long list of admirers but Man United appear to be the side leading the race for his signature.
Ince said the 20-year-old has to consider whether manager Ole Gunnar Solskjaer has what it takes to take him to the next level.
Ince told Paddy Power said: “When it comes to transfers, it’s not just about the team, it’s about the manager.
“Let’s look at Raheem Sterling as an example, Pep Guardiola has turned him into a world class player through his coaching and guidance.
“Sometimes as a player, it’s about looking at a team’s manager and coaching staff and whether they’d take you to that next level. That’s a decision Sancho will need to make.
“We know that Pep is experienced in that area, we know he can improve a player. But can Ole Gunnar Solskajer? We don’t know that, whatsoever.
“We have no clue what he’s like at developing a player of that magnitude.
“He’s clearly trying to develop a young team, so that will help, but in terms of actually the man to man management and development of someone like Sancho, he’s a total unknown.
“We’ve not seen any evidence yet that he can take a player to the next level.
“Firstly, he’s not been at United long enough to know that, but also because in his previous jobs he’s not had players like that at his disposal.
“We’ve seen it with Pep, and we’ve seen it with Jurgen Klopp, and the best managers are the ones who can take a player to that new level and improve them.
“Ole’s not at that yet, it doesn’t mean he can’t do that, but we’ve not had that proof yet.
“To use myself as an example, when I went to Inter Milan, I became a far better player under Roy Hodgson.
“He truly took my game to a next level, I felt fitter, stronger, my awareness went up tenfold. That, plus the change in culture and experience that I had.
“What I’m saying is, Sancho needs to consider all of those factors, culture, environment, team and ultimately the manager.”