Four goals from Mt Barker in the final term guided them into their first Great Southern Football League reserves grand final since 2013.
The Bulls booked their place in the 2020 decider against Royals after defeating Railways, the same team they lost the 2013 decider to, at Tigerland in horrid conditions on Sunday. Trailing by 10 points at the last change, the Bulls produced an inspired last quarter, kicking 4.3 to nothing to run out 17-point winners.
The Tigers led by seven points at the first change before being going scoreless in the second term, as the rain came down, to trail by two points at the long break. The Tigers booted the only two goals of the third term but were unable to hold off a rampaging Bulls outfit, who prevailed 7.7 (49) to 5.2 (32).
Royals have entered their fourth straight reserves grand final and will be in search of their first premiership since 2017 after shrugging off North Albany, 9.8 (62) to 2.5 (17).
A five-goal-to-one second half from Royals colts against Albany has kept their hopes of a fourth grand final win in the past five season alive as they won their preliminary final, 8.7 (55) to 5.7 (37). Railways will look for grand final redemption against Royals after downing North Albany, 4.10 (34) to 2.1 (13), on Sunday.
Six goals from Albany forward Tobyn Lowry against Mt Barker helped his side progress to the 16s grand final while Royals proved too strong for Denmark-Walpole in wet and windy conditions, winning 12.11 (83) to 0.4 (4) to set up a showdown with Sharks.
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