They led 31-10 at North Harbour Stadium at halftime after a wonderful patch of dominance to end the first half.
But they collapsed in a heap in the second spell, committing silly errors and stringing almost nothing together in attack.
Moana Pasifika, playing their first game at their new home venue and cheered on wildly by their fans during Culture Round, capitalised by dominating the second half with power and passion.
They ended up scoring five tries to the Highlanders’ four but were let down by goal-kicking.
A second straight victory, following their upset over the Blues, will be gratefully accepted by the Highlanders, and they did step up with courageous defence when needed.
Nevertheless, one suspects coach Jamie Joseph will have some reasonably furrowed brows when he reviews that second half.
The Highlanders could scarcely have asked for a better start after the teams had performed their respective challenges.
Two players who were not in the original starting XV combined for the simplest of tries after 90 seconds.
After the ball came wide from a scrum, Michael Manson showed his acceleration and balance to put the wind up three defenders, and Nathan Hastie was on hand to score the first points.
Sam Gilbert added the conversion and a penalty and it was 10-0 before you could blink.
The next 15 minutes, however, belonged to Moana Pasifika as they got their forward pack rolling, and tries were chalked up by massive prop Sione Mafile’o and fullback William Havili.
Moana looked to be steaming while the Highlanders looked a bit flustered and started to strike some discipline issues.
But that all changed in a stunning seven-minute period during which the Highlanders took control.
They were under intense pressure in the 31st minute when winger Caleb Tangitau took the wind out of the home side’s sails with a 90m intercept try, his third of the season.
Almost immediately, Moana first five Jackson Garden-Bachop made a hash of a catch, and Highlanders midfielder Tanielu Tele’a read the situation smartly to snaffle and score.
When Hastie peeled off a huge punt, turnover king Timoci Tavatavanawai stole possession, and lock Mitch Dunshea scored a rare try, the Landers were away laughing.
Ardie Savea did not find it funny.
The All Blacks star, wearing No 7 but playing No 8, leaped high early in the second half to grab a poor Taine Robinson kick and showed his speed on a 40m burst to the line.
There was a long delay to the game when Cameron Millar, who had only been on the field a couple of minutes as Robinson’s replacement, went down heavily after appearing to be knocked out by a charging Danny Toala.
While Millar’s health was of gravest concern, the Highlanders’ composure also seemed to take a hit.
They made a bunch of unforced errors and lost all cohesion on attack.
Moana Pasifika came roaring back and closed the gap when Havili got his second, though there was a good amount of doubt over whether he had got it down cleanly.
There was absolutely no doubt about the barnstorming finish from Semisi Tupou-Tae’iloa when the Moana loosie sent a message to the Highlanders, who let the Southlander slip through their fingers, and gave the home side a late sniff of victory.
The Highlanders managed to get the ball and wind down the clock, but there is no doubt this was a game that left them with more questions than answers.
Rising Highlanders fullback Finn Hurley was a late scratching with a quadriceps injury.
Gilbert moved to fullback and Manson made his second Super Rugby start on the wing.
The Highlanders now enjoy a bye week before hosting the Hurricanes on March 14.
Super Rugby
The scores
Highlanders 31
Nathan Hastie, Caleb Tangitau, Tanielu Tele’a, Mitch Dunshea tries; Sam Gilbert 4 con, pen
Moana Pasifika 29
William Havili 2, Sione Mafile’o, Ardie Savea, Semisi Tupou-Ta’eiloa tries; Patrick Pellegrini 2 con
Halftime: Highlanders 31-10.
