The Rebels needed to beat the Force by at least four points to earn a play-off berth ahead of the NSW Waratahs and Toomua calmly slotted the conversion after the match-winning try.
It looked like the Force would earn some sweet revenge on the Rebels by claiming their first win of the season.
In a heart-stopping final minute it appeared Melbourne’s reserve hooker Efi Ma’afu had scored but referee Angus Gardner said he had no clear vision with the TMO ruling the ball had been spilt backwards.
However, play had continued with Cabous Eloff picking up the ball and planting it next to the post, with the TMO awarding that effort.
That gave the Rebels a 32-30 lead, however, a win wasn’t enough, with Toomua’s conversion required to seal their maiden finals appearance.
“A little bit of relief and just really proud of the boys, we stuck at it there,” Rebels captain Dane Haylett-Petty said.
“Credit to the Force, for a long period of the game there they were on top of us and yeah, it was a great effort to fight back and score that try.”
It was an action-packed match with three players given yellow cards and the teams going toe-to-toe for the full 80 minutes.
Matt Philip looked liked he’d scored in the 78th minute but again there was no clear view of the grounding.
The Rebels will meet the Queensland Reds in the qualifying final next Saturday.
The winner of that will meet the Brumbies in Canberra on September 19.
It’s the third year in a row that Melbourne’s hopes of a finals berth have hung on a final-round result, and it looked like 2020 would continue their form of falling short.
The match on Saturday came three years to the day that the Perth-based Force were sensationall y axed from Super Rugby – with Melbourne keeping thei r place instead.
Force hooker Andrew Ready looked to have been the the unlikely hero, scoring a try either side of halftime from a driving maul.
The Rebels took a 20-13 lead into the second half but the Force showed their never-say-die attitude to claw their way back and set up the sensational finish.
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