Manchester City centre back, John Stones believes playing in four competitions will hamper the club.
The Etihad Stadium club sustained their first loss of the season last week, losing 4-3 to Liverpool.
And despite Guardiola ringing the team on occasion, Stones believes battling for the quadruple is strenuous at best.
“We obviously wanted that [to go undefeated in the league], and I’m sure every team does, but it’s such a difficult thing to do,” the England international told UK newspapers.
“The four competitions we’re still in, the amount of games compared to some other teams, you know it takes a toll, no matter how much you rotate the squad.
“I think sometimes you’ve got to hold your hands up and say, ‘we gave it our best shot’, which we did. I think we’ve just got to move on.”