Marty Banks' last-gasp penalty earned Highlanders a surprise 20-17 victory over Chiefs at Waikato Stadium.
The title hopefuls from Hamilton enjoyed most of the possession but had to fight back hard to level after solid kicking from Isaac Sopoaga and Patrick Osborne's try gave Highlanders the upper hand on Friday night.
Two penalty tries, both converted by Aaron Cruden, were not enough as Banks capitalised on a late foul from Sonny Bill Williams to grab all four points for the visitors.
Chiefs drew first blood with Cruden making up for an early penalty miss by successfully kicking between the posts in the fifth minute.
They were quickly pegged back, though, as Sopoaga steered home a 20th-minute penalty after Liam Messam was pinged for knocking on.
And when Ben Tameifuna was caught offside eight minutes later, Sopoaga duly doubled up to give the visitors the lead.
Highlanders extended their advantage to eight points in the 36th minute as Osborne slipped past three defenders before crashing over.
Although Sopoaga missed the subsequent conversion, he would nail a penalty on the stroke of half-time to make it 14-3 heading into the break.
Chiefs worked quickly to fight back following the restart and a 48th-minute penalty try was promptly converted by Cruden to slash the deficit to just four points.
The hosts regained the lead in the 58th minute, Highlanders disintegrating near the try-line to concede a penalty try which Cruden converted to edge the hosts ahead.
However, with only four minutes remaining, Banks drew the visitors level with a penalty after Sam Cane played the ball on the ground at a ruck.
Chiefs looked like settling for a disappointing draw but they would be denied even that grain of comfort as Highlanders snatched victory at the death.
When Williams was pinged for going off his feet at a ruck, Banks held his nerve to steer the ball over the black dot, thus sealing a dramatic win for the Dunedin club.