Blake Harper continued his strong start to the season to help South Wagga hit back from their first loss.
Harper finished unbeaten on 55 as the premiers made 6-230 from their 40 overs.
He then took three wickets as Kooringal Colts couldn't quite match it with the competition favourites.
Not even a century from Dave Bolton was enough for Colts to cause an upset at Harris Park.
Stand-in South Wagga captain Luke Gerhard admitted there were a few anxious moments in the 17-run victory.
"It was a tight one," Gerhard said.
"Dave Bolton batted very well, I dropped him early on, but apart from that he hit the ball very clean and the best I've seen him hit them in a few years.
"It was very dangerous and could have cost us the game."
Bolton made 118 at the top of the order but struggled to build partnerships as teammates fell around him.
He and Keenan Hanigan (28) combined for a 58-run stand, but former Blue Nate Mooney (23) was the only other Colt to score more than 12 in the chase.
"That helped us in a way as we could try to give Dave a single at times to try and bowl at the other bloke," Gerhard said.
"Obviously he's a smart cricketer and wasn't falling for that, Keenan batted pretty well but the just lacked that one partnership to go with Dave and really stick it to us."
However Harper's efforts with both bat and ball continue to impress.
South Wagga set him a good platform with Warren Clunes (61) elevated to opener.
It was a move that worked as he put on 110 with Alex Smeeth (42) for the first wicket.
Then Harper came to the fore.
"He's hitting them as good as anyone I've ever seen," Gerhard said.
"He's pretty focused on what he's doing, he's confident in what he's doing at the minute and in my eyes he's the best batter in the comp."