Porterfield's start to his one-day career has been Hussey-esque, already with two centuries to his name. He came back from the recent World Cricket League in Kenya as the tournament's second-highest scorer and averaged 110.66 in his five matches. He took part in the ICC Under-19 World Cup in Bangladesh in 2004 and then spent time at the ICC Winter Training Camp in 2006, later captaining Ireland A that year. While his graduation into the full side has surprised nobody, his immediate success has given Ireland huge cause to be hopeful as they look to the future. An excellent 85 in the 2007 World Cup helped Ireland beat Bangladesh and led to interest from Gloucestershire. However, a first-class deal hasn't arrived yet and time is running out so Porterfield has to be content with the role as Ireland's key batsman. His consistent returns during the 2007 season, including a career-best 166 against Bermuda, were a key part of Ireland's continued success against the Associates. He signed a two-year contract with Gloucestershire at the end of the 2007 season.