One of the striking features of Manchester City's strong start to the season was who their best players were.

Pep Guardiola was warning before the beginning of the campaign that all would not be rosy, yet they won the Community Shield and dropped just four points from their first nine Premier League matches as well as taking seven points from their first three Champions League games. Absences to key players including Rodri, Phil Foden, and Kyle Walker were brushed off because others stepped up to take the initiative.

Erling Haaland set off like an express train scoring goals for fun and Kevin De Bruyne started with intent before injury struck him down, but there were also strong performances from Rico Lewis, Josko Gvardiol, Manu Akanji and Mateo Kovacic. A tight defence and a prolific Haaland made for an excellent combination.

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What those players all had in common were they were fresher than the rest. Haaland and Lewis hadn't been at the Euros and three of the other four hadn't lasted long past the group stage, with Akanji reaching the quarters but recovering quickly to be a mainstay in the City side early on.

What was a solid backline stared chopping and changing every week as more defenders disappeared off to the treatment room, and Gvardiol, Lewis and Haaland are now particularly knackered by virtue of them being used so often. This has been a key advantage lost, and is particularly evident when up against sides that don't have European football and can have more days to prepare.

"Bournemouth and Brighton play one game a week. Six or seven days a week to prepare one game. Give me that! Gimme gimme! Give me that!" said Guardiola last month.

"The Premier League is real? No, I play 20 more games a season than you. But I am not complaining because, sorry, we won six Premier Leagues doing that. Why did we win? We were fit."

City haven't been fit for about two months now, and they have lost any freshness they had. Unless they suffer a surprise exit from the Champions League before the knockout rounds, it is unlikely to come back.

Unless of course City spend in January. Nobody will be available for cheap in the circumstances but the logic of signing players will be not just that they can improve the XI and the squad but that they can also help those already at the Etihad by allowing them more of a breather than they will otherwise get.