The NSW Waratahs were ahead at halftime against the Chiefs on Friday, and just 25 minutes after the break found themselves 32 points behind.
They never recovered and lost the Super Rugby fixture 51-14 in Wollongong.
The Waratahs were abysmal in the second half, conceding six tries and 38 unanswered points as the Chiefs won for the first time in NSW since 2007.
It was the most points the Chiefs have scored away against NSW, the second-most ever in Australia and their biggest win anywhere against the Waratahs.
The bonus-point victory saw the Chiefs jump from seventh to first on the competition ladder.
NSW led 14-13 at halftime before All Blacks and Chiefs halfback Brad Weber stunned the Waratahs with two tries in two minutes after the break.
The onslaught continued through Sean Wainui, Lachlan Boshier, Solomon Alaimalo and Anton Lienert-Brown who also scored second-half tries.
The Chiefs ran with the wind and had all the momentum early in the opening spell on the back of a 6-1 penalty count as Aaron Cruden slotted two penalties and Shaun Stevenson scored for a 13-0 lead.
But the Waratahs rallied and stormed back into the contest as Karmichael Hunt set up fill-in skipper Kurtley Beale to score on 25 minutes.
Hunt also set up their second try after he took a crash ball and managed to transfer possession to Jack Dempsey who crossed out wide.
Consecutive conversions from rookie No. 10 Will Harrison gave the Waratahs an unlikely lead in the 33rd minute.
But it was all downhill from there as the relentless Chiefs kept NSW scoreless in the second half while piling on 38 straight points to secure an emphatic victory.
Chiefs 51 (Brad Weber 2, Solomon Alaimalo, Lachlan Boshier, Anton Lienert- Brown, Shaun Stevenson, Sean Wainui tries Aaron Cruden 3, Kaleb Trask 2 cons Cruden 2 pens)
Waratahs 14 (Kurtley Beale, Jack Dempsey tries Will Harrison 2 cons)