Damien was primarily a right-handed middle-order batsman with a 'classical' technique, known in particular for his elegant strokemaking square of the wicket on the off-side and through the covers. Martyn was also an occasional medium-pacer and distinguished fieldsman primarily in the covers who was capable of creating spectacular run-outs. He also very occasionally kept wicket at first-class level. He was named man of the series in the Border Gavaskar Trophy in 2004, to help Australia defeat India on the subcontinent for the first time in more than 30 years, and was named in early 2005 as the Australian Test player of the Year at the annual Allan Border Medal presentations.
In the 2006 Champions Trophy Tournament, Martyn won back-to-back man of the match awards against England and India. He also played an important unbeaten innings in the final against the West Indies to help Australia win the tournament for the first time. He was Australia's leading runscorer in the tournament.