And Pochettino says that sort of situation would be the reality for Spurs too if Kane's head is ever turned.
Kane has been in sensational form for Mauricio Pochettino's men over the past few years and ended 2017 with 56 goals in all competitions for club and country during that calendar year.
Tottenham dominated all through the first half but failed to score.
But he concedes it would be tough to keep his best player if he wants out.
Tottenham made sure there would be no upset in the second-half however, as Harry Kane scored twice before Vertonghen found the back of the net with a deflected long-range effort to leave Spurs 3-0 up just eight minutes after the deadlock had been broken. Look what happened with Cristiano Ronaldo at Manchester United, with Zinedine Zidane at Juventus, with Luis Figo at Barcelona.
"I think it is a massive example or massive point to show how this business is, how hard it is for the clubs to keep their best players", Pochettino said of the Coutinho transfer. If another club pays the type of money [Barcelona] pay, how do you stop it?
Asked specifically about Kane, Pochettino said: 'I think Harry is special, so special, because he loves Tottenham and he feels Tottenham. The player needs to choose to stay here, you can not force the player to stay here. "So it's important that we must achieve everything we want together". Of course, Harry is a special player.
"But we need to be careful and clear in how we manage him".
"For me it's very important", Winks said.