The visitors won the toss and elected to bat, with openers Jayden Rosin (22) and Tristan Watson (33) putting together an opening stand of 29 before Rhys Bradley (2-22) struck to dismiss Rosin.
Swans star Asantha Singappuli was the new man to the crease, and while he put on 60 in partnership with Watson, he was unable to replicate one of the brilliant big knocks that he has so often produced this season, dismissed by Nondies skipper Kyeran Ellery (1-22) for 26 to leave South two down for 89.
Rathika Rajakumara replaced Singappuli in the middle and guided the Swans to a total of 184 after posting 44 of his own, although Xavier Wishart (3-39) and Patrick Doyle (3-20) struck with regularity in the second half of the innings to ensure the target remained reachable for their side.
With ball in hand, South removed opener Doyle early as Nondies looked to get started, Although Karim Marcelle and Archie Sussex combined for 65 runs before Sussex met his demise, caught and bowled by Swans skipper Ben Eade for 41.
Sam O’Shea made an important 28 as Nondies looked to be in control, cruising at 2-135, before Watson turned the game for South, snaring three quick wickets to reduce the home side to 5-164.
Rosin and Mitchell Stephens also claimed another wicket each to see the home side stumble to 7-171, still needing 13 for victory but with opener Marcelle unbeaten at the crease.
Eleven run were needed off the final over for Nondies to secure the win, with Marcelle belting seven from the first five balls to finish on 64 not out, although a single left Broden Wishart facing the final delivery with a boundary needed to win.
Rosin managed to safely secure the win for Echuca South, however, delivering a dot ball and ensuring his side leapt inside the top four with three rounds to play.
The Game
Echuca South 10-184 (Rathika Rajakumara 44, Tristan Watson 33, Patrick Doyle 3-20) d Nondies-Cohuna 7-181(Karim Marcelle 64 not out, Archie Sussex 41, Tristan Watson 3-32)