Tottenham manager Mauricio Pochettino says he is “very disappointed” that head of recruitment Paul Mitchell has decided to leave.

The pair worked together at Southampton and Mitchell followed Pochettino to White Hart Lane in November 2014.

But he has handed in his resignation, three weeks before the end of the transfer window, with a Tottenham statement saying he will leave at “a future date to be mutually agreed”.

Pochettino said: “I feel very disappointed with his decision. It’s his personal choice. You know we have a relationship from Southampton and I feel very disappointed but when some person takes some decision and it’s personal, what can I do?

“He is still working with us and will carry on. We’ll see what happens. We need to finish the three weeks working together and try to do the best business for the club. Then we’ll see what happens.

“Did I try to persuade him to stay? It’s obvious that’s what happened. But when you take your choice and personal things happen there’s nothing to do, only to respect his decision but carry on working.

“He’s with us, he’s in the office. Last night we shared a dinner with all the squad and he was with us. Nothing has changed for the moment, but this is the most important thing - that we keep working in the same way that we were before.”

Spurs kick off their Premier League campaign at Everton on Saturday, and Belgian centre-back Jan Vertonghen is fit after recovering from a knee injury sustained during Euro 2016. His countryman Mousa Dembele is unavailable due to suspension - for the first four games of the season - while Heung-Min Son is representing South Korea at the Olympics.

The challenge of competing for the title again will be difficult, given the cash spent by some of Tottenham’s rivals. However, Leicester won the crown last term and Pochettino is a firm believer that money isn’t everything.

“Every season in theory there are a lot of clubs that can contend for the title, and then it’s how teams spend money, and you can put the teams in the table from one to 20,” he said.

“But you never know - football is not mathematic and it’s not an ordinary business. The important thing is I am very happy with my squad, with the new signings and the youngsters. I think we will carry on with the same process we started two years ago.

“I needed a lot of meetings after Australia to talk about different things. It’s true we were all disappointed with the way we finished the Premier League.

“We need to show we are clever and learn from our mistakes. There’s not a lot of change in the changing room and squad and I think that can help us.”

Pochettino continued: “As a manager and a coach you can improve from your mistakes. We have a big challenge ahead to repeat our performance, to improve and for a lot of players the Champions League is a new competition.

“It will take more energy than the Europa League and we will have to manage it in a different way to last season. You can feel everyone is excited to compete.

“We have an exciting game against Everton - a great team with a good new manager. We have an exciting season ahead with the Champions League after a long period for the club and I think it’s all positive.”

Pochettino refused to provide an update on Tottenham’s interest in Marseille winger Georges-Kevin N’Koudou, who seemed set to join the club earlier in the summer, with the Spurs manager once again stressing his policy of not commenting on transfer rumours. But the Argentine confirmed there may be new arrivals.

“Yes, maybe yes,” he said. “We are open to adding one or two players - or maybe no-one. It’s important for us to respect our process.

“If we have the possibility to sign some players that can improve us then we are open, but I think it’s very difficult to find players with this profile because we already have very good players, and because of the way we work and our philosophy.”

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