Dunne returns to Eastlands for the first time since making a £6million switch to Villa in August after nine years at City.
City splashed out on Joleon Lescott and Kolo Toure in the summer but Dunne has proved his worth, making the PFA team of the year, and he could now clinch a Champions League spot at the expense of his former club.
The Republic of Ireland international said: "We've got a really big game against City. If we can pick up a win it will be an interesting last day of the season. I'm looking forward to it.
"It's good that it's worked out that it's such an important game for both clubs. It's something to look forward to and hopefully we can get the right result on the day.
"It's big for City. They're in front of their home crowd. They have to be in the Champions League - so the pressure's probably on them.
"They're expected to go out and win whereas we've come from nowhere over the last couple of weeks and we've given ourselves a chance.
"We're going in on a high, we've kept a couple of clean sheets, and we've won our last three games."
Dunne has hailed the character his side have shown in bouncing back from the 7-1 defeat at Chelsea to collect 13 points from the last five games.
He added: "A lot of people just classed it as the end of our season when we lost to Chelsea.
"But we still felt there were games there to win and we thought we could put a run together and keep that challenge going for fourth.
"It's turned out that way. We've given ourselves a chance with two games to go.
"But then that is the strength of the team, keeping going even when things have appeared to be going against us. We have always dug in."