In 2010 Mayhew was selected for the North Harbour development team[1] and played for the side in that year's ITM Cup.
[2] In 2011 he left New Zealand and, with a recommendation from former All Black and current North Harbour forwards coach Craig Dowd,[3] joined Harlequins.
Mayhew broke his ankle in 2011/12 preseason training, but eventually debuted for Quins in the second round of the LV Cup against Sale.
[4] He had limited opportunity for first team rugby in his first year with Quins, but was dual-registered to Championship side Esher to gain experience.
[6] He was on the brink of an international call up for Australia, having impressed in Super Rugby with ACT Brumbies and his scrum ability put him on Test coach Michael Cheika's radar.