Sunderland boss O'Neill wary of Man Utd 'revenge' motivation today
The Red Devils won their final game of last season at The Stadium of Light.
Sunderland fans cheered and taunted United with a City-style 'Poznan' celebration.
"If it had been in reverse and City had lost out, I think our fans would have cheered United," said O'Neill.
O'Neill's side visit Old Trafford after a midweek morale-boosting win over Reading.
And he said: "We can go there with confidence.
"The expectation from others would not be great but that doesn't matter.
"We have to go and compete and I think the players are genuinely looking forward to it."