Definitely man city v Spurs and I think Spurs were 3-0 ahead at half time and city had a man sent off. Came back and won 4-3 with a man down. Was the best game I've ever seen. It was when Keegan was in charge of city. 2004.
http://news.bbc.co.uk/sport1/hi/football/fa_cup/3447235.stm