Denis Joseph Irwin (born 31 October 1965) is an Irish former professional footballer who played as a full-back from 1983 to 2004. Born in Cork, Ireland, he is best known for his long and successful stint at Manchester United, where he established himself as one of the most important players in the United team that won a host of domestic and European trophies in his time there between 1990 and 2002. He has been regarded by Alex Ferguson as, pound for pound, his greatest ever signing. Earlier in his career he played for Leeds United and then Oldham Athletic, and finished his career with a two-year spell at Wolverhampton Wanderers. Irwin was capped by the Republic of Ireland national side 56 times, scoring four goals and featuring in the side that reached the second round (last 16) at the 1994 FIFA World Cup. Irwin is the joint most successful Irish footballer in history, a record he shares with fellow Manchester United stalwart Roy Keane, having won 19 major trophies in his career.