What game were you watching? Hodgson came on with Matterson and Hopgood deep into their first stints, and RCG ten minutes into his second. Makatoa came on for Matterson after Naden's try, five minutes later. Matterson had played 66 minutes straight at that point. Murchie came on for Hopgood at the 72nd minute (during the Doueihi stoppage), after Hopgood had played a single 52 minute stint. Matterson came back on for Makatoa almost immediately after that when Tupou scored. At that point Klemmer and Utoikamanu had only been on for 12 minutes (after nearly an hour's rest) and were still carving up.
But really our problem was not controlling the ball. That makes fatigue much more of a problem, regardless of your rotations.