Hammett started regularly for both Canterbury, and the Crusaders in 1998, with the latter he won his first Super 12 title. The 1998 Super 12 final was played against the Blues at Eden Park; Hammett said of the match "If we'd been polled in that week, and had to give an honest answer, most of the boys, deep down, would probably have thought that the Blues would beat us." Despite this, the Crusaders defeated the reigning champions 20–13. Hammett was rewarded with a New Zealand trial, where he captained his team. He was subsequently selected for New Zealand A and played against Tonga.