A brace by Adam Rooney and goals from Wade Elliott and Nathan Redmond earned Blues a 4-0 win at Bramall Lane and a place in the fifth round of the FA Cup.
"It was a really good all-round performance," the Blues boss said after the game.
"I'm as delighted with the clean sheet and the performance as I am with the goals.
"We had to weather a bit early in the game. They were certainly a threat but then we got into our rhythm and the timing of our goals was important.
"We're enjoying playing football and that breeds a certain amount of confidence.