De Bruyne was the subject of a nasty tackle from Crystal Palace midfielder Jason Puncheon on Sunday, and the Belgian was reported to be a doubt for the game on Tuesday, however, despite being in pain, the ex-Chelsea man started against the Hornets and put on a man of the match display.
Speaking after the game, Guardiola was full of praise for the attitude that his star man showed, and claimed that the Belgian insisted on playing despite his injury, as quoted by Sky Sports.
"Kevin showed great character," Guardiola said.
"He said 'I want to play, I want to play' even though he has problems with his ankle. He showed us a lot of things - he gave an outstanding performance."
Guardiola also spoke about the importance of bouncing back after dropping points against Palace, and claimed that his side could have scored five or six against the Hornets on Tuesday.
"It was excellent, brilliant. We started really good and the second half was really good again. It was a good reaction after dropping points at Selhurst Park.
"We faced this team really well. Three more points, simple as that.
"We created lots of chances to score five or six, but it wasn't to be. The aim is to be better than the opponent in every game and we did it."
Up next for City is Burnley in the FA Cup, and with key games coming thick and fast Guardiola is expected to rest some of his key players for the fixture.