Manchester United's rising tally of injuries this season and the Premier League club's busy run of fixtures ahead have left manager Erik ten Hag lamenting that the top-level football schedule has gone beyond what players can handle.
Denmark duo Christian Eriksen and Rasmus Hojlund added to United's injury problems over the international break, with Lisandro Martinez and Casemiro already among long-term absentees.
The record 20-time top-flight champions sit eighth after picking up 21 points from 12 matches, for their worst start to a season since 1962.
Under the new format from the 2024-25 season, the Champions League group stage will expand to 36 teams from 32, playing in a single-league format. Each team will play a minimum of 10 games, instead of the current six, against 10 different opponents.
"Every manager is complaining about the schedule," Ten Hag told reporters. "But still, they keep adding games to the schedule.
"Next year they add again two games (in the new Champions League format) and the limits are ... we already achieved the limits. I think we already crossed the limits of what players can handle."
United face a crunch week away from Old Trafford, visiting Turkish side Galatasaray in the Champions League on Wednesday, followed by a trip to sixth-placed Newcastle United at St James' Park in the Premier League on Saturday.
"And then what we see now in the first 12 Premier League games, the physical standards are even higher in comparison to last year. You have a choice to make. Either you match it by training and preparation, or you drop off," the Dutchman said.
"So that is a decision that every club has to make, every team has to make, every individual has to make."
United take on Everton, which last week became the first Premier League club to be deducted points for breaching financial sustainability rules, at Goodison Park later on Sunday.
Everton have dropped to second-from-bottom from 14th after an independent commission imposed an immediate 10-point deduction.