On the final day of January, Manchester City know they have a little over 72 hours to complete any remaining transfers.

Progression in the Champions League was a huge boost financially but it also highlights the need for reinforcements in certain positions ahead of a play-off with Real Madrid or Bayern Munich. If City get through that, they will face Bayer Leverkusen or Atletico Madrid, with future opponents potentially including Inter Milan, Juventus, Arsenal, Barcelona and Liverpool.

If City want to go far in the Champions League, they would surely prefer to have stronger options at full-back and in midfield. Ederson of Atalanta is liked at City, but there are clear hurdles to any deal. He is integral to Atalanta and they are reluctant to sell this month, while his goal vs Barcelona on Wednesday reinforced his importance to them.

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Atalanta will see their own path in the Champions League and look to get as far as possible. They could face Brugge or Sporting in a play-off, Lille or Aston Villa in the quarter-finals, and then maybe Liverpool, Barcelona or PSG in the semi-finals. A run like that could be lucrative and Ederson would be crucial to it.

But City's need for a holding midfielder is clear, and Guardiola has admitted he cannot rely on John Stones for support in that area due to his fitness record.

"Of course it is an important position. Every position is important," Guardiola said about a holding midfielder earlier this week. "We have replaced Rodri with two players who are not proper holding midfielders and we will see in the future what we have to do."

There is also the full-back question, with Matheus Nunes starting six games in a row amid Kyle Walker's exit and Rico Lewis dropping out of first team contention. Nunes has shown promise out of position - against Chelsea and Ipswich for example - but also has made some bad errors against Brugge and PSG.

He clearly isn't a right-back, and Real Madrid will lick their lips at the prospect of lining up Vinicius against Nunes rather than Kyle Walker. So will Bayern with Leroy Sane, Kingsley Coman and Serge Gnabry in their ranks.

Juventus' Andrea Cambiaso is a name that has persisted this month, with similar hurdles with that particular deal in the final days of the window. He would be expensive, but would improve the squad - although reports in Italy suggest he will remain there until the summer. He was left out of the final Champions League League phase fixture with a knock.

In terms of exits, City must clear up the situation with James McAtee, who has taken plenty of steps forward this month after looking to be on the brink of leaving in December. Guardiola reiterates that he hopes McAtee could stay, but the arrival of Omar Marmoush and return of Oscar Bobb will add further competition to his chances of minutes.

There is talk of interest from Bayer Leverkusen - a potential Champions League quarter-final opponent - and other Bundesliga sides. As much as City want to keep him, McAtee has a decision to make before Monday's deadline.

City didn't intend to lose anyone from their first team this month and that stance remains. But they equally won't stand in the way of anybody who wants to leave - like in the case of club captain Walker.