That perfect record saw them move into the top half of the draw and play knockout rugby for the main prize.
Day two kicked off with a quarter-final match against the Southerners, whom they beat 24-0 thanks to tries from former Waikato rep Navi Sikivou, Epeli Vukivuki, Mosese Kalougata and Harrison Pett.
They kept their perfect defensive record in the semifinal with a 26-0 victory.
Tries to Josh Blaikie, Kalougata, Ezekiel Murray and Mogi ensured the comfortable win and a final against eight-time defending champions Jam Boys, who were also undefeated throughout the two-day event.
It turned out to be all that a final should be – a tight, back-and-forth tussle between the top two sides.
Hamilton Old Boys emerged winners by 26-19, with a hat-trick for Sikivou being the highlight and Kalougata also dotting down for another try.
The team return home with preparations well underway for the Waikato club rugby season, where HOB will be looking to go one better than 2023, when they were beaten in the semifinals by eventual champions Hautapu.
A new-look coaching lineup awaits for the 2024 season, with former Melville head coach Wayne Bootten making a return to Hamilton Old Boys after a stint there in 2015-17 with the colts side.
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