[2] He worked on improving his goal kicking and defensive skills, which led some to suggest Brett's primary weakness is in his defence, thus impeding his progress to higher levels.

With regular first-five Daniel Carter being unavailable for much of the season due to the World Cup conditioning program, Brett seized his chance in the number 10 jersey and finished 2007 as the Crusader's top scorer with 90 points.

He continued his good form into the 2008 competition, scoring a try and picking up the Man of the Match award in the Crusaders brilliant 54–19 victory over reigning champions the Bulls in Pretoria,[5] before breaking his collarbone in a 55–7 win against the Cheetahs; the injury sidelined Brett for around six weeks.

[6] He was signed by the Blues for the 2010 and 2011 seasons,[7] On 29 July 2011, Brett left New Zealand to join Japanese club Toyota Verblitz in the Top League on a two-year contract.

[9] On 17 April 2014, Brett left Bayonne as he signed for another French side, Lyon in the Top 14 on a two-year contract from the 2014–15 season.