Opal won 6-44 to 3-35, with Tim Comer and Kerry Walker winning all three sets they lined up in.
Stacey Kay picked up the best results of the day for Karramomus, winning two sets and just going down to Lynette Gibbs and Emily Briggs while playing alongside Lisa Bell.
Meanwhile, Old Students thumped Shepparton North in the other pennant match.
Evan Cooknell and Georgie Moore were the only Shepparton North players to record a set win.
Lemnos forfeited its match against McEwen Reserve White.
In the lower grades, McEwen Reserve Green aced clubmate McEwen Reserve Gray 8-53 to 1-33.
Gray won plenty of games, but couldn't take more than the one set, which was Helen Malcolm and Rosemary Hemetsberger defeating Megan Lock and Kellie Morrison 6-5 in the women's doubles.
St Andrew's held on in a nail-biting one-game win over Central Park White.
The biggest margin in each set was 6-4, with nine exceptionally close sets meaning the win came down to the final 6-5 set win by Arthur Trinder and Carmel Wileman over Mark Preston and Claire MacGill.
St Brendan's managed to trump Bunbartha in a tight affair.
The Saints finished three games ahead, 5-42 to 4-39, with a mixed doubles comeback not enough to push Bunbartha's nose in front.
Steve O'Connor and Tessa Smith and Georgie Michel and Jacklyn Lamb won 6-3 in their mixed sets to help inspire a comeback for Bunbartha, but St Brendan's’ Paul Harlow's and Kellie Crosier's 6-3 win kept their side in it.
Shepparton North Red recorded a five-game win over Karramomus and their clubmate Shepparton North Gold defeated Central Park Blue 7-48 to 2-34.
Old Students 5-44 defeated Undera 4-32, while Murchison forfeited against McEwen Reserve Orange.
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