Golden Square Black took advantage of their home tables to secure a spot in the Bendigo Billiards grand final.
They drew with Eaglehawk 2-2, but took the upper hand to win on points, 845-747.
The elimination final was also decided on points, which gave Castlemaine the advantage over VRI Gold, 964-948.
Breaks on the night were made by John Schenck (63,41) and Henry Smyth (40).
The final spot in the grand final will be decided tonight with Eaglehawk hosting Castlemaine in a tough preliminary final encounter.
In the B-grade competition Castlemaine hung on to a win a nail-biting preliminary final.
Despite losing the first two matches, Golden Square Blue put up a hard-fought effort to win the remaining two matches, but fell short of a win on points, 717-709.
The division's grand final will be decided on Tuesday night, with Castlemaine and minor premiers VRI set for a championship battle.
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