East Wagga-Kooringal didn't let a slow start stop them from completing a strong back end of the year.
The Hawks won their last eight games to claim their first reserve grade title since completing a hat-trick of flags in 2016.
North Wagga fired early to take a seven-point lead after the first quarter.
Captain Luke Adams thought it was a nervous start after the week off but was pleased with how the Hawks responded.
"The legs were heavy early and we had to wait for our second wind but we started to play a bit more composed footy, trusted ourselves and trusted each other," Adams said.
"We took the mentality to just chip away, as we weren't going to blow them away and knew it was going to be a scrap for four quarters and slowly got on top."
After conceding three goals in the first term, the Hawks only let two more past them in the 9.9 63 to 5.7 37 victory.
EWK fired to start the second quarter, kicking three goals in four minutes to put themselves in front.
The five goals to nil term saw them out to a 22-point lead at the main break and while the Saints were able to reduce the margin by one point at the last change the Hawks never looked like giving up their advantage.
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Coach Dan Bromham was an emotional figure watching on before in playing the first grade grand final but said the victory meant a lot.
"I can't thank them boys enough," Bromham said.
"They stood up when they had to."
Joe Scott capped off his return to the club following a year of rugby union being being judged best on ground.
East Wagga-K: 1.6, 6.7, 7.8, 9.9 (63)
North Wagga: 3.1, 3.3, 4.5, 5.7 (37)
Goals: (EWK) D Hitchens 2, C Polson 1, James Scott 1, T Gillard 1, C De Piazza 1, L Adams 1, S Burge 1, M Carroll; (North Wagga) N Fitzgerald-Holmes 2, T Gaynor 2, R Martyn.
Best: (EWK) M Beasley, C Hommes, J Scott, T Hengsen, H Leddin, S Burge; (North Wagga) T Pattison, B Curtis, T Gaynor, D Karlberg, N Fitzgerald-Holmes, R Martyn.
Best on Ground: Joe Scott (EWK)