The Belgian was injured on international duty and was missing from the squad for the weekend win over Arsenal.
For the match against the Gunners, Pep Guardiola opted to switch his formation to deploy three at the back - a deviation from his tried and tested four-man backline.
The back three of Kyle Walker, Ruben Dias, and Nathan Ake kept a clean sheet in the 1-0 win, too, so Guardiola could trust them to do so again in the same line-up.
Aymeric Laporte, Oleksandr Zinchenko and Benjamin Mendy are all out injured which forced the manager's formation change in the first place.
Joao Cancelo was deployed in the right-wing back role with Phil Foden on the other side, and although that could be the case against Porto again, the latter is by no means a conventional wing-back, instead opting to cut inside centrally.
In the continued absence of Gabriel Jesus, Sergio Aguero will lead the line despite continuing his fight back to full match fitness.