Mauricio Pochettino says Gareth Bale would not have been allowed to leave Southampton under the current regime.
The Spurs superstar, who will face his former club on Saturday, graduated from Southampton's academy and played for the south coast club as a 16-year-old.
Spurs signed him at the end of his maiden season and he has blossomed into one of the world's finest players since, this week picking up a clean sweep of gongs for the season's standout player.
Theo Walcott and Alex Oxlade-Chamberlain were also developed at Southampton before moving on to Arsenal and Pochettino insists that in future no young stars will need to be sold on.
"With this current club's ambition, dedication and vision for the future, it would be very hard for Gareth Bale to leave this club," he said.
"Right now, our mentality is to keep our best players and we spoke about that with Nicola (Cortese, executive chairman) from the first day.
"We want to keep our greatest talents but at the same time now we need more time in order to develop our greatest talents as it happened with Bale, Oxlade-Chamberlain and Walcott.
"Now we need to be able to keep our greatest players, our greatest talents like Luke Shaw and James Ward-Prowse, in order for them to develop their football and become top footballers.
"It is a shame we don't have these three players available for Southampton now but that is our project for the future."
Pochettino admits his players will be up against it when they face Bale at White Hart Lane.
"Bale is a very decisive player - an amazing player because of his speed, strength and goalscoring abilities," he said.
"He has shown that throughout the season this year so I rate him very highly. Our collective game needs to be very strong on Saturday. We can't just focus on Gareth Bale - there are other players in that team that can raise their game.
"In a collective sense, we need to be very focused and mentally ready as we need to be in every single game that we play in the Premier League."