The Citizens captain, who confirmed last week he will leave the club at the end of the season, grabbed a goal and an assist as his side boosted its hopes of qualification for Europe's elite club competition next season.

Goals from Eberechi Eze and Chris Richards put Palace in the driving seat midway through the first half, but De Bruyne's 25-yard free-kick gave City hope.

Omar Marmoush drilled home to drag City level before the break, and Pep Guardiola's team then produced arguably its best performance of the season in the second half.

Mateo Kovacic fired in from the edge of the box to make it 3-2, then James McAtee latched on to Ederson's searching pass to round Dean Henderson for City's fourth.

Fellow youngster Nico O'Reilly saw a volley deflect in late on to add some gloss to City's win, while Palace suffered its first defeat in 11 away Premier League games.

With Newcastle United and Chelsea not playing until Monday (AEST), City took advantage to move above them into fourth, while Oliver Glasner's side stays 11th.

City boss Pep Guardiola hailed De Bruyne's performance after the playmaker sparked City's comeback.

"[It's] the Kevin we have known for many years," Guardiola said. "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.

"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."

One concern for City was Ederson going off midway through the second half with an injury, with the Brazilian having earlier provided his fourth Premier League assist of the season when he set up McAtee.

Guardiola was not sure of the extent of the injury.

"I don't know," he said of Ederson. "He made the pass and said he felt something and couldn't continue."

Palace lost a Premier League game in which they led by two or more goals for the first time since August 2022, also away at City, and manager Oliver Glasner was disappointed with the manner in which his side conceded.

"The defeat really hurts because when you're up by two and scoring the third, we had a fantastic start," he said. "But we conceded the goals too easily.

"We didn't defend at our top level, so we can do this better. A team like Man City will punish it. We were not on our top level today defending, and that's why we conceded too many goals."

"We have to accept City are a top team. When you are not at your top level, they can always find the gaps, and they are able to score a goal. Especially after their first, they got quicker, and after the second, they had their rebound. I think after the first goal, it was tough.

"The players did their best, but we will learn from this game. When you play a team like City, you have to be at your top level in defence."