Tottenham Hotspur manager Mauricio Pochettino has bemoaned the difficulty of teams retaining their best players amid interest from the sport's biggest and richest clubs.
The Argentine boasts a number of impressive players at Spurs, who are often the subject of intense transfer speculation in the world's press.
In January, Liverpool reluctantly sanctioned the sale of talisman Philippe Coutinho to Barcelona, who in turn saw Neymar depart Camp Nou for Paris Saint-Germain last summer.
Speaking after Tottenham's 3-0 win over AFC Wimbledon in the third round of the FA Cup, Pochettino highlighted the challenge facing every club in the modern game.
"I think it's a massive example of how this business of football is, and how difficult it is for clubs to keep their best players," Pochettino told Sky Sports News.
"Liverpool is historically one of the best clubs in the world, but when a player like Coutinho wants to leave, it is difficult. Look what happened with Cristiano Ronaldo at Manchester United, with Zinedine Zidane at Juventus, with Luis Figo at Barcelona. There are a lot of examples.
"That is why it is so important how you care for your players. That's why you need to anticipate things. It's so important to work on the human side, to try to create a project where the players feel comfortable and happy to be with you.
"But today, when the player decides to leave, it's what happens. If another club pays the type of money [Barcelona] pay, how do you stop it? I heard what [Jurgen] Klopp said. Our job is so difficult."
Harry Kane is one such player believed to be on the radar of some of the world's biggest clubs, including Real Madrid, although the striker has been compared by Pochettino to Roma stalwart Francesco Totti with regards to potentially becoming a one-club legend.
