A handful of narrow losses and one lonely win gave way to their first real shellacking of the year.
Everyone says Loftus Versfeld can be an ugly place to play at - and it should not be forgotten the Bulls are the defending champions - but not many were forecasting such a one-sided result.
The Highlanders pride themselves on character and defensive fortitude, but both were sorely lacking on the high veldt.
Forty-seven points are the most they have conceded since the Brumbies posted 50 in Canberra four years ago, and the margin of defeat was the heaviest since the Crusaders won 38-3 at Carisbrook in April 2007.
The grim reality is that the Highlanders are on track for the worst season in their history. They've never won fewer than three games in a season, and never lost more than eight.
All season, the Highlanders have been sustained by warm talk of effort and competitiveness, and consoled by the fact they are trying to rebuild with a ragtag collection of honest toilers.
But those sentiments are starting to become wearisome. Any more performances like the weekend's loss will erode some of the foundation of the rebuilding work.
The Highlanders were missing in action in the first 20min of the Bulls game.
Twice the Bulls out-flanked the Highlanders' hesitant defensive line and created simple tries, the first to fullback Zane Kirchner and the second to winger Akona Ndungane.
Poor discipline also gave Bulls kicker Morne Steyn a chance to extend the lead with the boot.
In fact, the Highlanders were so insistent on making referee Paul Marks blow his whistle you just knew a player was going to end up in the bin.
So it proved. Highlanders winger Fetu'u Vainikolo took out Kirchner in the air and was sent to the sideline for 10 min.
It was a dumb play by Vainikolo, just two weeks after he was yellow-carded for a late tackle against the Lions. His has been a spectacular rookie season, but he does himself no credit with his reckless approach to defence.
Of course, the Bulls scored in his absence, with good handling, fine support play and a poor effort at a covering tackle by Toby Morland leading to Kirchner's second try.
Six minutes after the break, the Bulls moved further ahead, with simple quick ball from a scrum putting centre JP Nel over the line.
The one consolation from a bad day at the office was that the Highlanders did not quit at this point.
They actually regrouped well for a time. Lock Hoani MacDonald started dominating the line-out, leading to more Highlanders possession, and No 8 Steven Setephano stopped trying to cut people in half and started playing with controlled aggression.
The backs also looked more likely through the second half, with centre Niva Ta'auso having one of his better games.
Chris King came off the bench to score the Highlanders' first try, and the second was from a fine run by lock Tom Donnelly, who clasped the ball, Meads-like, in one hand and barged his way through three tacklers.
But it was a false dawn. The Bulls immediately reasserted their dominance, coming home strongly with tries to Pedrie, Wannenburg and Ndungane.
Every team can have a bad day, as the Crusaders found out against the Chiefs, and this was certainly the Highlanders'.
They must find some way to avoid a repeat against the Stormers in Cape Town this weekend.
Bulls 47 (Zane Kirchner 2, Akona Ndungane 2, JP Nel, Pedrie Wannenburg tries; Morne Steyn 4 conversions, 3 penalty goals), Highlanders 17 (Chris King, Tom Donnelly tries; James Wilson 2 conversions, penalty goal). Half-time: Bulls 28-3. Referee: Paul Marks (Australia). Crowd: 12,988.
