Gundogan was man of the match for the 4-0 win.
De Bruyne said of Gundogan: "He's amazing.
"I think he understands perfectly the rhythm of the game and I think he has got that moment where he turns up in the box and it's very dangerous.
"He scores a lot of goals and the one-two with Erling (Haaland) started the game off for us.
"I've been playing for six years with him and he has been incredible in that period of time."