For the second time in a month, United was too strong for last year's premier, storming out of the blocks early in the round 18 contest.
The home side stunned Nagambie in the opening term to enter the first break with an eight-goal lead.
Nagambie co-coach Sarah Sanderson was left frustrated with the replica performance from the round 15 loss.
“It was pretty similar to last time,” Sanderson said.
“We let them get the lead and we couldn’t peg it back.
“We were about eight down at quarter-time, then it was pretty even.
“It’s frustrating we couldn’t put it all together.”
Sarah O'Sullivan's desperation and work ethic in the midcourt stood out for the Lakers, and sharp-shooter Bianca Willis was influential in the attacking end.
Saturday's loss means Nagambie finishes the season with a 12-4 record, while United enters the post-season with a 15-1 record.
“(Dookie) started much better and had better pressure,” Sanderson said.
“We need to start better, we can’t afford to give these teams a head start and then need to catch up.
“We need to play a full hour of netball.
“That will be a big theme for the next few weeks.”
In other games, Tallygaroopna clinched third position on the ladder with a 43-16 win against Lancaster.
Murchison-Toolamba crushed any chance of Shepparton East playing in finals with a 55-32 win.
Avenel ended its season on a winning note, defeating Violet Town 59-36 and Stanhope flexed its muscles to record a 105-13 drubbing of Longwood, the second time the Lions have passed the 100-goal mark this season.
Score: Dookie United 36 d Nagambie 31
KDL Finals first week
First Elimination Final at Longwood
Tallygaroopna v Merrigum
Second Elimination Final at Violet Town
Nagambie v Murchison-Toolamba
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