Hynes made his Test debut for the Wallabies as one of the two run-on wingers against Ireland in Melbourne on 14 June 2008. He had a very strong game and won the Player's Player award for the match against Ireland. Two weeks later, he went on to win the Man of the Match award in the first Test against France on 28 June 2008. In the second Test against France on 5 July 2008, Hynes scored his first try for the Wallabies in front of his home crowd at Suncorp Stadium in Brisbane. After playing in all six Test matches in the 2008 Tri Nations Series, Hynes received the Wallabies Rookie of the Year award, and toured with the Wallabies on the 2008 Spring tour.