London - Liverpool manager Jurgen Klopp believes too much demand is placed on international stars who have had barely any rest following the World Cup.
Klopp's men play away on Saturday against Tottenham who had nine players involved on the final weekend of the World Cup, less than a month before the start of their Premier League campaign.
The likes of England captain Harry Kane, midfielder Dele Alli, and victorious French skipper Hugo Lloris were thrown straight back into action by Mauricio Pochettino.
But Alli and Lloris are now sidelined by injury, while Kane has looked jaded in the opening weeks of the season.
"A good pre-season should be at least three or four weeks," said Klopp. "That is how it is, the body needs the time only to calm down from an intense season - they didn't have it.
"We ask too much from the players, we constantly want them ready and if they are not we are not happy. It is a weird situation.
"Now with the Nations League, international managers cannot rest players because it is a proper competition. It is a constant challenge for all of us."
Liverpool were less affected by the demands of World Cup action than their title rivals and it has shown in their fine start to the season with four straight Premier League wins to sit top of the table.
Unlike Spurs' England contingent, Klopp has bedded captain Jordan Henderson slowly back into action, while Mohamed Salah and Sadio Mane's early exits in Russia with Egypt and Senegal meant they had a few weeks of pre-season training.
Kane has been a constant scourge of Liverpool, scoring five times in seven appearances against the Reds, including twice in a 4-1 thrashing at Wembley last season.
And Klopp is sure Kane will find his best form, even if he hopes it comes after Saturday.
"We all knew it after the World Cup, especially after England came that far, they have had no rest," added Klopp.
"Harry played from the first match on, so maybe he had two weeks holiday - that is nothing.
"He is a physical worker, he uses his body every day. He cannot get a rest match-wise but he will find his form and maybe at the weekend."