The Bulls now progress to the grand final in a fortnight on countback after finishing the regular season as minor premiers.

Pirates hit the ground running and opened the scoring in the 13th minute through forward Hayden Griffiths before fullback Brad Thrift extended the lead, winning the race to the ball to score in the corner after a clever chip-and-chase effort five minutes later.

It gave the visitors a handy 10-point lead, but the Bulls, making some uncharacteristic errors, finally got their hands on the ball in good field position and Tim Mitchell charged through some flimsy defence to score out wide.

Fullback Toby Knight converted the try and added a penalty goal five minutes before half-time to lock the scores up at 10-all at the break.

Bulls forward Mitchell Parker put the home side in front for the first time when he finished off some clever lead-up work from Adam Duncan who ran 30 metres before he drew the fullback and sent Parker on his way to score in the far corner.

Again, Knight added the extras from near the sideline to put the Bulls in front by a converted try.

But the Pirates were not to be denied and Ryan Withertin fortuitously charged down an Angus Mactavish clearing kick and found the ball lodged between his arms and his stomach.

He crossed under the posts and with halfback Kerrod Binge adding a penalty goal it was all locked up at 17-all with 13 minutes remaining.

Mactavish was again in the thick of the action minutes later when he intercepted a loose Pirates pass, but he was ruled to be penalised and given a yellow card after the referee ruled a professional foul.

Binge again added the penalty goal to put the Pirates back in front before Bulls fullback Knight converted a 25-metre penalty goal with two minutes remaining to again level the scores.