The Highlanders ended the Bulls' 20-game winning streak at Loftus Versfeld on Saturday with a shock 35-28 bonus-point win over the defending Super Rugby champions.
Wing Kade Poki scored two tries and flank Adam Thomson continued his phenomenal start to the season with a try of his own as the visitors led from start to finish to make it three wins from three starts this year.
The Bulls flattered to deceive in their opening two games this season and were found horribly wanting, especially on defence, as the Highlanders ran their hosts ragged.
The visitors played smart rugby, moving the ball around at pace and keeping it far away from the Bulls' formidable tight five.
The Highlanders now top the New Zealand conference and share the overall tournament lead with the Sharks.
The surprise package of the early season, the Highlanders continue to impress with their all-action expansive style, while the Bulls were a pale shadow of the team that dominated the Super 14 last year.
Big names are letting the Bulls down: Put your hand up Wynand Olivier, Pierre Spies et al. Missed tackles, dropped passes, jugging to breakdowns....this is not the way to defend the title.
The visitors took an early lead when Thomson scored in the corner after just five minutes.
The Bulls struggled to find their rhythm as Morne Steyn and visiting fly-half Robbie Robinson traded penalties to leave the Highlanders 11-6 up at half-time.
The visitors extended their lead through a Josh Bekhuis try shortly after the restart with 36-year-old Tony Brown (on for Robinson) adding the extras.
Poki's first try, scored under the post after a scything run through midfield off an inside ball from Brown, took the lead to 25-6.
The Bulls pulled two tries back through Flip van der Merwe and Fourie du Preez after some trademark phase play but Poki's second try in the corner left the hosts fourteen points down with nine minutes left.
Bjorn Basson scored in the dying minutes to set up a grandstand finish as the Bulls pushed for a draw, but it was not to be.
The Bulls will have some introspection to do during their bye week while the Highlanders travel to Cape Town to take on the Stormers.
Tries: Van der Merwe, Du Preez, Basson
Cons: Steyn 2
Pens: Steyn 3
Tries: Thomson, Bekhuis, Poki 2
Cons: Brown 3
Pens: Robinson 2, Brown
Yellow cards: Stegmann (Bulls - 40th min - foul play); Soakai (Highlnaders - 73rd min - hands in the ruck)
Bulls: 15 Zane Kirchner, 14 Gerhard van den Heever, 13 Jaco Pretoruis, 12 Wynand Olivier, 11 Bjorn Basson, 10 Morne Steyn, 9 Fourie du Preez, 8 Pierre Spies, 7 Dewald Potgieter, 6 Deon Stegmann, 5 Victor Matfield (c), 4 Danie Rossouw, 3 Werner Kruger, 2 Chiliboy Ralepelle, 1 Gurthro Steenkamp.
Replacements: 16 Derick Kuun, 17 Rossouw de Klerk, 18 Flip van der Merwe, 19 Juandre Kruger, 20 Ruan Snyman, 21 Francois Brummer, 22 Stephan Dippenaar.
Highlanders: 15 Ben Smith, 14 Siale Piutau, 13 Kendrick Lynn, 12 Shaun Treeby, 11 Kade Poki, 10 Robbie Robinson, 9 Jimmy Cowan, 8 Nasi Manu, 7 Alndo Soakai, 6 Adam Thomson, 5 Josh Bekhuis, 4 Jarrod Hoeata, 3 Chris King, 2 Jason Rutledge, 1 Jamie Mackintosh (c)
Replacements: 16 Brayden Mitchell, 17 Bronson Murray, 18 Tom Donnelly, 19 John Hardie, 20 Aaron Smith, 21 Tony Brown, 22 Telusa Veainu.
Referee: Stuart Dickinson (Australia)