Manchester City know how difficult it is to buy in the January window.

Clubs will hike prices because they know it is a market for emergency shoppers more desperate than they are in summer, and players are less likely to want to move mid-season. To give one example, would Ederson at Atalanta be as keen to move now that his side are sitting top of Serie A and flying high in the Champions League?

The Champions League has thrown up two fresh issues for Txiki Begiristain this month because of the changes to the competition. What was a difficult month to get deals done in the first place has now become even harder.

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As Tottenham manager Ange Postecoglou has highlighted, now the fact that the group stage of the new European tournaments run until January 30 means that clubs are now more keen to hold onto players than they once were. Whereas in previous years, clubs would have known since early December whether they would be in the knockout rounds, now the whole of January is a slog for them all to stay in the fight until the end given the league table.

“It’s a bit more challenging this January because sometimes you would find maybe a couple of clubs are out of the Champions League and maybe think they can release a couple,” Postecoglou said. “That doesn’t exist now because all European competitions are in the balance. That probably adds another layer of difficulty to it.”

Just as Ederson may be less keen on moving this month, Atalanta will be less keen on selling him as they look to secure their path to the last-16 in the Champions League. City have to be looking at players who are playing in European competitions, but that leaves more uncertainty.

The other issue with the group stage finishing later is that anyone City manage to sign will not be able to feature in two of their biggest games in January: Paris Saint-Germain away and Club Brugge at home. UEFA rules dictate that the squad can only be added to ahead of the knockout phase, meaning that any players bought before those games would not be able to feature in them.

City should of course be looking at their signings for the long-term, but given it is their dire injury situation that means they are looking to break habit and spend in January, the need is most urgent over the next month when they are looking to ensure they make the play-off for the last 16. With two matches to go, they sit 22nd out of the cut-off line of 24 with games against 25th-placed PSG and 19th-placed Club Brugge left to play.

It won't stop City wanting to do business, but the Champions League has made it harder for the Blues to complete deals this month.