Following a falling out with his provincial coaches regarding his attitude – which almost drove him to retire from the game – D'Arcy was left out of the international setup for three years. His second game for his country came on 17 November 2002 as a late substitute in Ireland's 64–17 win over Fiji. He made a further three appearances as a substitute during 2003. He was not selected for the Irish squad for the 2003 Rugby World Cup in Australia, but was picked for the Leinster team during the absence of its World Cup players. It was then that he came into his own, playing some of the best rugby of his career at fullback/wing, where he displayed delightful skill in running from deep and finishing off the moves that he had started. After the World Cup, an injury to Brian O'Driscoll, his Leinster teammate, saw D'Arcy move to outside centre, where he made a great impression.