The Croatian defender revealed he only discovered he would start a few hours before kick-off but insisted he was ready to seize the opportunity after a frustrating spell on the sidelines.
"I was surprised, I didn't expect my name in the starting XI – (I found out) two, three hours before kick-off. At the end of the day you need to be ready and I'm happy to be back. We all know that there are three games left, happy to be back and get some minutes,” Gvardiol told Premier League website.
"I'm getting older, I'm more experienced than a couple of years ago. All I try to do is play as well as I can.”
Gvardiol was also full of praise for teammate Phil Foden, who delivered an impressive performance against the visiting Londoners.
"We know (Phil Foden's) quality, how good he is in small spaces. He's really good and we know he's capable of doing these things. It was exactly what we needed and great assist,” he continued.
"It would be too unreal to score a goal in my first game since my injury - maybe the next one.
"It hasn't been easy. After I got injured I told myself to accept it as a new challenge. I'm glad to be back, I wouldn't say I'm at 100% but I need games, I need minutes. That's normal."