Mauricio Pochettino admits Tottenham have struggled to find players “who can help us" during this summer’s transfer window.

With less than a week until Thursday's 5pm transfer deadline, Spurs are the only Premier League club yet to make a signing, despite uncertainty over the futures of a handful of their current squad.

Spurs are in advanced talks with Aston Villa over 21-year-old Jack Grealish, though manager Steve Bruce said on Friday that Spurs were "nowhere near" his valuation, and they also hope to sign a holding midfielder and a forward in the coming days.

Pochettino has admitted he does not know how many signings Spurs will get over the line and, asked if it could be none, he said: "Yes. We are working so hard but still we are like it's the first day of the transfer window – with no signings.

"I think I am not the person to explain it," he added. "Of course, people expect the manager to explain that but, for different reasons, it's been difficult to add players who can help us. But in the last week many things can happen."

Spurs' executive director Donna-Maria Cullen – the second most influential board member behind chairman Daniel Levy – said last week that Pochettino was relaxed about Spurs' lack of transfer business and suggested that the club do not need to spend big because of the quality of their academy .

The Spurs manager insisted that he can never relax in his job but admitted that he would turn to Spurs' young players – like 21-year-old Luke Amos and 17-year-old Oliver Skipp, who impressed in pre-season in the USA – if they do not make signings.

"I'm not relaxed because I'm a coach and you cannot be relaxed," he said. "I think you need to be confident and trust in the people we have and the way that we work.

"Of course, football is all about adding more quality every season like our rivals are doing. If we cannot do that, we need to try to be creative and, of course, the help of younger players will be amazing and they showed they can help us if, in the end, we cannot sign players."

Spurs still hope to offload unwanted strikers Vincent Janssen and Fernando Llorente, while Toby Alderweireld, Danny Rose and Mousa Dembele all face uncertain futures.

Josh Onomah, Harry Winks and Victor Wanyama all miss Saturday's friendly at Spanish club Girona with injury.