Home boss Manuel Pellegrini admitted the 5-0 scoreline in Wednesday night's FA Cup replay was harsh on the visitors, Blackburn having held their own until conceding the opening goal of the game in first-half stoppage time.
City's superior quality then showed as they were able to introduce star striker Sergio Aguero from the substitutes' bench.
Blackburn manager Gary Bowyer said afterwards: "I've nothing but pride for them. Our boys didn't freeze, they kept going and wanting the ball.
"We were playing against a world class team, probably the best in the world at the moment."
Bowyer was without two key men for the game as injuries ruled out Scott Dann and Jordan Rhodes, both of them linked with January moves away from Ewood Park.