Set 311 to win, Moama was in early trouble at 2/16 but a magnificent 119 from Jordan McGregor saw the home side finish on 7/315.
The win has fifth-placed Moama equal on points with fourth-placed Echuca with just one round of the home-and-away season to go.
In that final round, Moama faces bottom side Echuca South and are heavily favoured to win.
That would mean Echuca would need to defeat second-placed Tongala to be assured of playing finals, not an easy task considering Tonny’s excellent form this season.
On Saturday, Echuca would have gone into the second day’s play full of confidence and more than 300 runs to play with.
That confidence would have strengthened after Chris Russell removed Anthony McMahon (6) and Jack Russell (0) with just 16 runs on the board.
But that just brought McGregor to the crease who almost single-handedly steered the game back in Moama’s favour.
He shared a 124-run third wicket partnership with Brad Jones (68) and a 104-run partnership with Alistair McCann (60).
By the time McGregor was dismissed with the score at 7/293, he had smashed 14 fours and one six to have Moama in sight of the target.
Will Devlin (31no) and Darcy Elliott (9no) guided the team home in the final stages to complete a remarkable run chase.
For Echuca, Russell and Josh Preston both finished with figures of 2/52.
The result leaves Echuca facing the real prospect of missing the finals unless they can defeat Tongala.
It will be a big ask after Tongala nearly produced an outright result at the expense of BLU.
Defending 245, Tongala was ruthless on Saturday as they routed BLU for just 61.
Matt Ohlsen was the pick of the Tonny bowlers, finishing with the incredible figures of 5/9.
BLU was forced to follow on and fared a little better, ending the day on 6/134 and staving off an outright defeat.
Josh Wood led the way with a resolute 59 not out.
In the other matches, Brad Goodman took 6/26 as Cooma (9/340) dismissed Echuca South for 175.
Amila Gunathilaka was the top scorer with 45 batting at number 10.
Kyabram Fire Brigade’s Mick Mattingly (5/43) ripped through the Rochester middle order to guide the Flames to an 87-run victory.