The Bulls survived a mighty scare from the Force as they fought back to overcome the Australian outfit 36-26.
22-26 down with ten minutes remaining, the men from Pretoria managed to create a rolling maul that allowed Jean Cook to cash in at the tail.
And what had looked like being a shock loss ultimately turned into a bonus-point win when tighthead Werner Kruger crashed over at the end.
The Bulls had come out in good form in the rain and didn't take long to get on the board when fly-half MornÃ¨ Steyn backed himself on the right side from 20 metres out. Steyn showed decent pace to go over in the corner but could not convert from the touchline, with the Bulls 5-0 to the good after two minutes.
However the Force struck back on ten minutes following strong work in the air from Nick Cummins. The Wallaby wing rose highest to claim Sias Ebersohn's tester and from the recycled ball the former Cheetahs fly-half was back in the pocket to cut the lead down to two. It was a warning shot to the Bulls.
The home side soon responded thanks to an initial break from young wing Sampie Mastriet. His line bust from halfway led to the Force offending at a resulting breakdown and when referee Jason Jaftha sounded his whistle, Steyn called for the kicking tee to cancel out that earlier Ebersohn drop-goal.
Ebersohn was back on the scoreboard on 26 minutes though after the Bulls backline came offside. And when the Force number ten then slotted a 60 metres shot at goal on the half-hour, the Australians were suddenly one point ahead.
That lead lasted just four minutes though as Steyn made it 11-9 due to captain Matt Hodgson entering a maul from the wrong side. Despite holding the slender lead, the Bulls fans who travelled to the stadium were not happy.
The mood looked to have improved when Bjorn Basson announced himself on the game with a scintillating finish that saw him cut inside from 20 metres out for what he thought was the game's first try. But following a TMO referral, the try was cancelled out due to Lionel Mapoe having thrown a forward pass.
Steyn did knock over three points as consolation on the first-half hooter in a spell that held more than a feeling could go away from the Western Force.
14-9 soon became 14-12 though only a minute after the restart when Ebersohn slotted his second drop-goal of the fixture. But the Bulls, who were without Francois Hougaard and Chiliboy Ralepelle for the second-half, then clicked into gear as, from Steyn's pass, Sampie Mastriet raced into the right corner.
Steyn went from hero to villain seconds after missing his conversion of Mastriet's try when he found a pass swooped upon by Angus Cottrell, who raced clear from 65 metres for the try. Ebersohn's conversion levelled the scores in what was a frantic opening to the second stanza.
The Australians then came close to causing the upset, with Angus Cottrell and Toby Flynn crossing the whitewash within ten minutes of each other, and Ebersohn was on target with both conversions to hand his side a seven-point lead.
The Force held on to their advantage for fifteen minutes until the Bulls made a gutsy fightback.
Steyn succeeded with twelve minutes left on the clock before Cook, who replaced flanker Jacques Potgieter, scored in the 70th minute, with the fly-half converting the try.
The Bulls then finished the match off on a high with prop Kruger scoring his side's bonus-point try at the death.
For the Bulls:
Tries: Steyn, Mastriet, Cook, Kruger
Con: Steyn 2
Pen: Steyn 4
For the Force:
Tries: Cottrell, Lynn
Con: Ebersohn 2
Pen: Ebersohn 2
Drop: Ebersohn 2
Bulls: 15 Zane Kirchner, 14 Sampie Mastriet, 13 Lionel Mapoe, 12 Wynand Olivier, 11 Bjorn Basson, 10 MornÃ¨ Steyn, 9 Francois Hougaard, 8 Pierre Spies (c), 7 Arno Botha, 6 Jacques Potgieter, 5 JuandrÃ¨ Kruger, 4 Flip van der Merwe, 3 Werner Kruger, 2 Chiliboy Ralepelle, 1 MornÃ¨ Mellett.
Replacements: 16 Willie Wepener, 17 Frik Kirsten, 18 Grant Hattingh, 19 Jean Cook, 20 Jano Vermaak, 21 Louis FouchÃ¨, 22 Jan Serfontein.
Western Force: 15 Will Tupou, 14 Nick Cummins, 13 Winston Stanley, 12 Kyle Godwin, 11 Alfie Mafi, 10 Sias Ebersohn, 9 Alby Mathewson, 8 Richard Brown, 7 Matt Hodgson (capt), 6 Angus Cottrell, 5 Hugh McMeniman, 4 Toby Lynn, 3 Salesi Ma'afu, 2 Nathan Charles, 1 Pek Cowan.
Replacements: 16 Heath Tessmann, 17 Tetera Faulkner, 18 Sam Wykes, 19 Ben McCalman, 20 Chris Alcock, 21 Mick Snowden, 22 Jayden Hayward.
Referee: Jason Jaftha (South Africa)
Assistant referees: Lourens van der Merwe (South Africa),Sieg van Staden (South Africa)
Television match official: Johan Greeff (South Africa)