Recently re-signed midfielder Teihorangi Walden will miss the Highlanders' clash against the Waratahs this Saturday due to concussion.
The 24-year-old experienced concussion symptoms in the lead in to the match, and young back Sio Tomkinson will get a crack in the starting line up.
Tomkinson has had limited opportunities with the club this season, though has shown glimpses of his ability when he taken to the pitch.
Having appeared in four of the side's 10 matches this season, Tomkinson will look to make the most of the extra minutes. His addition was one of four changes to the starting lineup who beat the Lions last round.
Aaron Smith returns to the starting halfback role, while loose forward Dillon Hunt and lock Jackson Hemopo move into the pack.