Bernardo scored with a header to secure a 2-0 win over Borussia Monchengladbach.
Asked if Bernardo was now matching the heights of the 2017/18 and 2018/19 campaigns, Guardiola said: "He's quite similar - last season maybe he dropped a bit, but every time he plays he is an exceptional player with exceptional quality."
And of Bernardo's heading ability, he added: "He's really good in the air! I've seen in the training sessions when you make an action for the header you have to use your body and he is strong and he is a good header, honestly.
"The goal was fantastic, the way he finished it. He has this special quality."