Waddle was left unimpressed by United for the 2-1 defeat today.
He told BBC Sport: "Looking at United today, has their performance been much different to last season? I'm not sure. If Louis van Gaal had been in charge of this he'd be getting hammered.
"In the first half City were excellent. United looked short on legs, not only at the start but all across the game. The hosts did put a shift in during the second half but City had that extra class.
"United looked one-paced and were a long-ball team towards the end. They ran out of ideas and City deserve the result."