A hard working half-back flanker who liked to run the footy, Twomey was recruited from the Ivanhoe Amateurs and was one of Collingwood's better players in the 1981 Grand Final loss to Carlton. Despite appearing in the Preliminary Final triumph twelve months earlier, Twomey was omitted from the Grand Final team, with Ricky Barham taking his place. He was a regular in 1981 and 1984, earning six Brownlow votes in '84. He was the nephew of Bill, Pat and Mick Twomey and the grandson of Bill Twomey Senior.