Mak chose City ahead of Chelsea when he was considering his move from Slovakia and Gibson told City's website: "It doesn't matter which side he pops up, he's always a threat. We do a lot of work on quick-break play and once Robbie is put through he's a real handful. If he gets his heels ahead he's difficult to stop.
"We can play better than that, but the attitude and application was great. We battled superbly. There are no poor teams left at this stage - we expected a physical duel and we got one. But we dug in and we handled it.
"Norwich performed very well and they did their club and their coaches proud. Sometimes you get a bit of luck, but you also make your luck by hard work and graft, and I thought we did that on Saturday."
City face Arsenal in the semifinals.