The width of a post was all that separated the Brumbies and the Cheetahs after an epic 15-13 home victory at Canberra Stadium on a freezing Sunday afternoon.
Cheetahs fly-half Riaan Smit had the chance to send the match into extra-time with the last kick of the game but watched on as his conversion attempt of Ryno Benjamin's last-gasp try from tight to the touch line thundered off the upright and put the Brumbies through.
Fifteen points from the boots of kickers Christian Lealiifano and Nic White ultimately sent the Brumbies into the Super Rugby semi-finals, and a date with the Bulls of South Africa on Friday, following a nerve-shredding afternoon in Canberra.
The Brumbies started brightly and were in front in the second minute as Lealiifano struck over a mid-range penalty after the Cheetahs strayed offside in midfield. It was the Cheetahs, though, who were to cross the whitewash first in their initial foray into the Brumbies 22.
Smit had missed a 10th-minute penalty attempt, his kick drifting wide of the upright, before the South Africans struck back. A mis-placed kick gave the visitors prime field position and, from the resultant line-out, they spread the ball wide where centre Johann Sadie picked the perfect line to ghost through and score out wide.
A brace of missed penalties from Lealiifano created tension in the ranks so it was with some relief that the newly capped Wallaby slotted his fourth shot at goal 10 minutes before the interval, to restore the Brumbies' lead at 6-5.
The Cheetahs continued to pose a threat on the sporadic occasions they entered the home half with fly-half Smit directing operations and looking to spread the ball wide at every opportunity. But the Brumbies defence was firm and the hosts went into the changing rooms at half-time with the narrowest of advantages.
It lasted barely seven minutes upon the resumption as the Cheetahs, sensing a famous victory in their first finals outing, continued the swinging momentum as Smit crashed over a long-range penalty from in front of the posts. The Brumbies responded in kind minutes later with an even bigger kick of their own as White bisected the uprights with a strike of pure power to delight the home fans.
At 9-8 with half an hour to play it was anyone's game and, sensing this, the Brumbies upped the ante, particularly at the set-piece. A dominant scrimmage yielded a fifth pot at goal for Lealiifano midway through the half and the centre clipped the ball over the posts to increase the lead to four points.
The Cheetahs conceded a raft of penalties with Lealiifano collecting another three points with 12 minutes to play. Cheetahs replacement Benjamin did eventually force his way over in the far left corner as the clock wound down but Smit was unable to kick the extras to win the match for the South African side.