Their 20-14 victory lifts them up to fourth place in Tennent’s National League Division 1 with 41 points from 14 games.
They’re now just one place and two points behind the Galashiels side, but the Netherdale outfit have three games in hand on them and also one on second-placed Biggar.
Kelso’s tries were scored by Frankie Robson and Murray Hastie, with Hastie and Dwain Patterson adding a penalty kick and conversion apiece.
Neil Turnbull and Simon Fairburn got Gala’s tries, with Craig Dods converting both.
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Kelso captain Andy Tait was chuffed with his side’s performance, telling Borders Rugby TV: “We’re delighted with that. Earlier in the season, we met them at Netherdale and we were a little bit disappointed with our own performance and we just needed to right some wrongs.
“It wasn’t a great spectacle, but at the end of the day I think the team that made less errors came out on top.
“The boys stuck in really well, and the defence came through in the end.
“Two wins against Gala and Melrose can’t be underestimated.
“They were really great performances.”
Gala captain Liam Scott added: “Credit to Kelso, they came out and they were fantastic in defence from the off.
“I felt like we applied pressure the whole game. A few decisions didn’t go our way, but that’s rugby. It was a close-fought game.”