City came from 2-0 down in today's early kickoff to win 5-2 at the Etihad, with De Bruyne scoring their opener to spark the fight-back.
Guardiola said afterwards: "I would say we played really good all game. We were 2-0 down and we created a lot and I said at half time we were playing good.
"Our momentum was sparked with a free-kick from Kevin and after that we played a really good game considering we were 2-0 down and considering how Crystal Palace have been in the past games."
On De Bruyne's performance, he continued: "The Kevin we have known for many years. I know he's struggled the last year and a half. He's free without pain and completely different. The way we played helped him a lot with incredible runners, the young lads, the full-backs."
On strengthening their top four chances, Guardiola also said: "We'll see tomorrow the position, it will be so tight. It will be until the end. Six games left, difficult games."
Ederson was forced off in the second-half and replaced by Stefan Ortega and Guardiola added, "I don't know. He made the pass and said he felt something and couldn't continue."