The Belgian defender believes that his experience from previous club Ajax, famous for their youth academy, has given him the skills to identify quality youngsters.
Vertonghen told the Evening Standard: "A few of them played in pre-season with us and they impressed me then. The guys who played last night (Wednesday) and those who came on in the second half are real quality players, very skilful and with a good mentality.
"I think that Ajax, for young players, is one of the best clubs in the world at which to develop, so I know good young players and we have them here at Tottenham.
"What I have seen here makes me think that all these players can eventually play for the first team."
Spurs travel to Old Trafford to face Manchester United in the Premier League on Saturday evening.