Tottenham boss Antonio Conte says Harry Kane is "really, really tired" after he was replaced in the second half of a Carabao Cup loss at Nottingham Forest.
The England captain Kane started the 2-0 defeat 12 days before his country's opening World Cup game against Iran.
England boss Gareth Southgate names his squad for the World Cup on Thursday.
"It was a problem of tiredness," said Conte, who stressed Kane would be OK. "It's only fatigue but it's normal because Harry played every game."
Kane made his 21st consecutive start for Spurs in the EFL Cup third-round match at the City Ground on Wednesday evening.
He was replaced after 59 minutes despite Spurs trailing by two goals, with Forest earning the win through strikes by Renan Lodi and Jesse Lingard.
Conte said Kane was "really, really tired", adding: "Yesterday we had a soft training session and at one point he stopped himself to recover energy."
Conte said he had waited until Wednesday morning before deciding whether or not to start Kane in this match.
"Other players maybe they could tell me, 'I'm tired and don't want to play and help the team'," he added.
"Another could be selfish and think for himself because in one week they have to play the World Cup. Instead, Harry Kane showed to be a really good man.
"But I repeat, it's normal, what's happening in this period."
England captain Kane, who is just two goals away from equalling Wayne Rooney's goal-scoring record for the national team, is a certainty to be named in Southgate's World Cup squad on Thursday.
England face Iran on November 21, before taking on USA and Wales in Group B.