Lock Tupou Vaa'i scored a hat-trick of tries as the Waikato Chiefs locked up top spot in the Super Rugby Pacific standings and home advantage throughout the finals with a 41-21 victory over the Otago Highlanders.

Runners-up for the last two years, the Chiefs did not hit the heights they have this year in their final regular season clash but always looked like having enough to get past a young Highlanders side on Friday night.

"Although the game wasn't perfect, we got the win," said Chiefs captain Luke Jacobson.

"We got the four points, and we're at the top, and we can change our focus to what's in front of us in the quarter-final next week now. Credit to the Highlanders. They were gutsy as tonight."

The Chiefs thrashed Moana Pasifika 85-7 last week and looked like running rampant again when they raced to a 19-0 lead inside the first 13 minutes under the roof at Dunedin Stadium.

Flanker Samipeni Finau went over to open the scoring before All Black Vaa'i crossed twice in the space of two minutes but the Highlanders gradually worked their way back into the game.

Prop Ethan de Groot got one try back from close range on the half-hour mark and, with Chiefs tighthead Reuben O'Neill in the sin bin, the ever-dangerous Timoci Tavatavanawai added another to cut the deficit to 19-14 at halftime.

Scrumhalf Xavier Roe raced away down the blindside to give the Chiefs the perfect start to the second half and replacement back Manasa Mataele gave them a 31-17 lead heading into the final quarter, but the Highlanders would not lie down.

Sam Gilbert ran onto a clever Tanielu Tele'a kick to score a try in his final appearance for the Highlanders seven minutes from time and they would have drawn closer had Cortez Ratima not come up with a brilliant try-saving cover tackle.

Vaa'i was not done yet, however, and he pounced on a loose ball from a goal-line drop out in the final minute to condemn the Highlanders to the wooden spoon for the first time since the second season of Super Rugby in 1997.