Mauricio Pochettino could be without most of his Tottenham Hotspur team for the club's season-opener against Newcastle United.
Nine of Pochettino's players were competition in the final weekend of the World Cup in Russia.
Hugo Lloris was in the victorious France side yesterday, while Harry Kane, Dele Alli, Kieran Trippier, Eric Dier and Danny Rose were involved with England, who finished fourth.
Tottenham trio Jan Vertonghen, Toby Alderweireld and Mousa Dembele part of the Belgium squad which won Saturday's third-place play-off.
Christian Eriksen, Davinson Sanchez and Heung-Min Son were also away at the tournament.
Jose Mourinho will not involve his World Cup players in Manchester United's season-opener, and Tottenham manager Pochettino must make his own judgement for the August 11 game against Newcastle at St James's Park.
"We cannot start the Premier League with our players that were in the World Cup, which is a shame for the most important club competition in Europe," said Mourinho.
"I think (three weeks) is the minimum that their body and soul needs, and which is the minimum for them to return and think about football again.
"To bring them back before that would be 'OK, I have you for the first match of the season, but maybe I don't have you in three or four months'.
"I think three weeks is the minimum they need, which means that they're going to be back in the week when the Premier League starts, which means they're not ready to start the Premier League, which is I think difficult to understand, where we could have one more week to prepare everybody."
Meanwhile, United manager Rafa Benitez only had two players – new signing Ki Sung-yueng and Aleksandar Mitrovic – at the World Cup.