Sources close to the club admit a final decision on whether to address one or both areas has yet to be made, but the growing expectation is that at least one new signing will arrive before the window closes.
An injury to Levi Colwill has heightened the need for defensive cover, though Wesley Fofana and Benoit Badiashile are expected to return soon. For now, Chelsea are relying heavily on Tosin Adarabioyo and Trevoh Chalobah - a situation Maresca fears could leave his side exposed.
After meticulous squad building and victory at the Club World Cup this summer, Chelsea are determined to avoid a late weakness derailing their domestic ambitions. Internally, there is even cautious hope of mounting an unexpected title challenge if the squad hits its full potential.
The goalkeeper position remains under review, with Robert Sanchez and Filip Jorgensen both vying for the No. 1 role. Some staff members, however, continue to push for a more experienced option. Chelsea have already failed in a bid for AC Milan’s Mike Maignan and, so far, resisted the temptation to move for Paris Saint-Germain’s Gianluigi Donnarumma, who is seeking a move away from the French champions.
Despite these concerns, Chelsea’s recruitment drive in attack remains active, with moves for Alejandro Garnacho and Xavi Simons still on the table - even though the forward line is already well stocked.
A decision on the centre-back and goalkeeper positions may go down to the wire, but Chelsea have a shortlist prepared for both roles and are ready to act swiftly should they choose to trigger a late-window push.
