The Woden Valley Rams edged out the Belconnen United Sharks 22-20 in a thrilling elimination final.
The Rams advance to next week's preliminary final, while the Sharks end their season after a heartbreaking loss.
Woden will face the loser of the major semi-final between the Queanbeyan Kangaroos and the Queanbeyan Blues in a grand final qualifier.
Woden’s first scoring opportunity came early when five-eighth Daniel Desmet executed a well placed grubber into the in-goal, trapping Sharks fullback Tristan Eldridge behind the line to earn a repeat set.
The Rams capitalised, with fullback Daine Spencer creating an overlap a few tackles later, allowing right winger Koko Salim to score effortlessly in the corner.
Sam Gash's conversion attempt was waved away, leaving the Rams with a 4-0 lead after the first 10 minutes.
The Sharks' first opportunity came when winger Connor Massen broke through and gained plenty ground from deep in his own territory.
As he was brought down, Rams hooker Adam Lucas was penalised for slowing down the ruck and was consequently sin binned.
Despite being a man down, the Rams' goal-line defense held firm against a threatening Sharks attack.
Belconnen eventually capitalised on the extra man advantage when lock-foward Jesse Bellchambers crashed over under the posts, putting his side ahead 6-4.
After a period of end-to-end footy with missed scoring chances from both sides, Rams halfback Josh Fattore took matters into his own hands, as he placed a grubber into the post, allowing him to regather and score. Gash converted, putting the Rams back in the lead at 10-6.
Woden rolled down the field again, with Fattore sending a cross-field kick that was batted down by Massen. Rams centre Lachlan Eveston kept the play alive, offloading to Spencer, who created space on the outside for Salim to score his second try.
Just before halftime, a shift to the left from 40 metres out opened up space for Gash, who won the foot race to cross for another Rams try.
Gash missed both conversions and the Rams went into the sheds with a 18-6 lead.
Belconnen needed first points in the second half to keep the game within reach, and they delivered.
A well executed shift to the left allowed centre Deakin Bright to slice through the defense and score. Zac Patch's conversion attempt was unsuccessful, leaving the Rams with an 18-10 lead after 47 minutes of play.
The Rams quickly responded, with Desmet delivering another precise grubber for Spencer, who outpaced Eldridge to score, extending their lead to 22-10 after the missed conversion attempt.
But the momentum soon shifted in favour of the Sharks as their big and mobile forward pack rolled up their sleeves.
Finding themselves within close range, the Sharks’ left edge proved dangerous once again, as a shift to the left found Eldridge, who delivered a beautiful cut-out pass to Massen, allowing him to score untouched.
Patch accounted for the heavy breeze, as the conversion attempt swung left to right and through the posts, reducing the deficit to a converted try with just over 10 minutes remaining.
Woden had a prime opportunity to seal the game as they found themselves deep in opposition territory.
After receiving a penalty for a high tackle, the Rams had the chance to extend their lead by 8 points but opted to go for a four-pointer.
The ball was knocked on off the tap, and Patch quickly picked it up and played on.
Spencer brought him down but lingered too long in the ruck, resulting in a sin bin that ruled him out for essentially the remainder of the game. The decision not to take the penalty goal was proving costly.
The Sharks marched down the field and had several attempts at the line, but all went begging.
The Rams then pushed into attacking territory, with a chance to seal the game, but Lucas' grubber from dummy half rolled over the dead ball line, gifting the Sharks a seven-tackle set.
The Sharks made the most of it, working their way downfield.
On the fifth tackle, Patch put up a kick that a Rams player fumbled, allowing Massen to scoop it up, giving the Sharks a fresh set close to the line.
With just over two minutes left, it was now-or-never for the Sharks.
They shifted right and got the ball to Eldridge. As he was being taken down, he managed to flick it to Tevita Aroha-Tuinauvai, who reached out to score in the corner, bringing the score to 22-20 in favour of the Rams.
Patch had the chance to tie the game with a difficult sideline conversion in windy conditions, but the attempt was waved away.
The Sharks had just under two minutes left to pull off a miracle.
In a chaotic final minute, the Sharks played hot potato, shifting the ball from sideline to sideline in search of space.
They worked their way to within 15 metres, with numbers on the left edge, but backrower Sonny Tupuola was brought down by a desperate tackle from Fattore.
In a last-ditch effort, Eldridge put in a grubber that led to nothing as the final siren sounded.
The Woden fans erupted as the Rams narrowly held on for the win, keeping their premiership aspirations alive.