It's been a busy summer transfer window at Stamford Bridge, with ten new recruits arriving through the doors in the shape of Pedro Neto, Kiernan Dewsbury-Hall, Filip Jorgensen, Tosin Adarabioyo, Marc Guiu, Renato Veiga, Omari Kellyman, Caleb Wiley, Mike Penders and Aaron Anselmino.
The Blues are also working on a deal for Atletico Madrid's Joao Felix, who previously enjoyed a loan spell in west London, as well as Victor Osimhen, with Enzo Maresca keen for further attacking reinforcements before the transfer deadline.
In terms of player departures, Ian Maatsen, Lewis Hall, Omari Hutchinson and Diego Moreira have been sold for a combined fee of around around PS103million, while Thiago Silva, Malang Sarr and Hakim Ziyech left the club on free transfers.
Atletico Madrid have been locked in talks to sign Conor Gallagher for much of the summer but Chelsea's unsuccessful pursuit of Samu Omorodion saw the move hit the rocks, with the England midfielder currently left in limbo.
Meanwhile, Lukaku - who spent last season on loan at Roma - has been offered to Napoli as a potential makeweight in a deal for Osimhen and Broja could be set for a switch to Ipswich.
It remains to be seen where Gallagher, Lukaku and Broja will be playing their football when the transfer window closes, but all three are absent for Chelsea's encounter with Premier League champions City.
Speaking at his pre-match press conference on Friday, Chelsea boss Maresca confirmed that Gallagher had returned from Spain but was training alone.
'Conor is back.
He is training apart,' Maresca told reporters.
'He is doing some medical tests and some training.
He won't be involved in the game.
'At this moment, he is trying to find a solution with the club.
''At the moment if I start to think I have 43 players it is not a good thing, I have 28 training with me,' he added.
The Blues are hopeful of getting an agreement over the line for Joao Felix which could, in turn, see Gallagher's move to Atleti finally come to fruition.
It's understood Chelsea's latest offer of PS39.
2million - plus PS4.
2m in bonuses - for Felix is close to Atleti's valuation of the Portugal international.
'He is doing very well, as you can see,' Atleti head coach Simeone told reporters when asked for an update on Felix's situation at his pre-match press conference this morning.
'His behaviour is what is expected of any footballer at Atleti.
.
.
commitment, training in the best way, ready for whatever is proposed to him and competing with team-mates.
'Time will tell if we can use him tomorrow or not.
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