Hamish Stewart's late penalty capped a stunning fightback from the Reds as they rallied to claim a first Super Rugby win of the season, beating the Sunwolves 34-31 in Tokyo on Saturday.

The Queensland side looked to be heading for a fourth defeat out of four when the Sunwolves led 21-5 at half-time at Prince Chichibu Memorial Stadium, but it was a different story after the break.

Jamie Booth, Rahboni Warren-Vosayaco and Dan Pryor crossed to put the Sunwolves in command, with a Liam Wright five-pointer all the Reds could muster before the interval.

The Reds came roaring back with three tries in the space of seven minutes midway through the second half, Brandon Paenga-Amosa claiming a double either side of Harry Hoopert finishing off a great move.

Keisuke Uchida took advantage of a Reds error from the restart to level in a pulsating encounter and Hayden Parker converted, then extended the Sunwolves' lead with a penalty seven minutes from the end of a thriller.

Brad Thorn's side came back again, though, Tate McDermott pouncing to score when an attempted clearance was charged down and although Stewart was unable to add the extras, he won it from the tee in the 79th minute.

The encounter between the Highlanders and the Crusaders in Dunedin was called off as a mark of respect following the terror attacks in Christchurch on Friday.