The Blues, seeking their second top-six scalp en route to finals, dropped their second game in a row, 55-37, to top-two side Rumbalara to be consigned to their fifth loss of the season.
A fast-starting Rumbalara jumped out of the blocks and it was its pace around the ball that Tongala coach Paige Wade pointed to as a key factor in the defeat.
“Rumba are a really quality side,” Wade said.
“We probably started a bit slow and they got a jump on us fairly early in the game. They play a very fast brand of netball.
“They were too good on the day by a fair way.”
Corey Drennan and Rose Hammond battled hard in Tongala’s back-court but, despite an improved showing after quarter-time, the Blues were no match for a Rumbalara side rebounding from just its second defeat of the year.
Rumba goalers Magi Hollis and Tash Atkinson led the way for the home side, while its back-court toiled hard to stifle the influence of star Tongala goal shooter Milly Brock.
The result means that, with two games to go, Tongala is likely to finish in fifth spot, three games clear of sixth-placed Mulwala and two shy of Moama in fourth.
Rumbalara looks all but certain to wrap up a top-two spot, two games clear of third-placed Nathalia.
In other results, Moama picked up a handy 37-goal victory over Congupna, while Deniliquin stayed undefeated with a 21-goal win over Barooga.