[1] He made his Super Rugby debut in 2005 for the Blues after being called into their squad as an injury replacement and appearing as a substitute in their final match of the season against the New South Wales Waratahs.

[1][2] In March 2010, he confirmed he had activated a get-out clause in his NZRU contract to sign a three-year deal to play for the Ricoh Black Rams in the Top League.

[6] Ellison captained the Junior All Blacks to victory in the 2009 Pacific Nations Cup, a year after winning the 2008 edition as co-captain of the New Zealand Maori, alongside Liam Messam.

[1][7] He was chosen as one of four new caps for the All Blacks 2009 end of year tour to Europe and made his first test appearance in the 20–6 victory against Italy in Milan.

[1][7][10] He is the grandson of All Black Vince Bevan, who played six tests for New Zealand between 1949–50, and son of rugby coach Eddie Ellison.