The NSW Waratahs are in the box seat to claim Australia's guaranteed Super Rugby finals berth after ending their Canberra woes on Friday night.
The Waratahs now have a massive psychological edge over the ACT Brumbies, nudging their way to a 13-10 win in the capital.
The loss threatens to blow the Brumbies out of the finals race, with both teams level at the top of the conference and the Waratahs having a game in hand.
The Brumbies must now travel to South Africa needing to win all of their remaining games to keep their title hopes alive.
The Waratahs were superb in clinging on in the dying stages, withstanding a last-minute attempt to steal the match.
David Pocock played with a discloated finger, Michael Hooper had blood flowing from his head and Rob Horne was sent to the sin bin in a fiercely contested Australian derby.
"It does hurt, it's a very disappointing loss at home but we're proud of the effort," said Brumbies skipper Stephen Moore.
"We had a lot of opportunities to score in the second half but couldn't get over the line, the Waratahs deserved to win tonight.
"It was very, very physical, I thought we fronted up. Both teams had opportunities at the breakdown and they came off the best there."
In a match with Wallabies battles in every position, the biggest Canberra Stadium crowd of the season was treated to a traditional rugby arm wrestle.
Both teams will meet on Saturday morning for a Wallabies World Cup-planning meeting as they put Super Rugby rivalries aside.
But there was plenty of fire on the field even though there were plenty of mistakes and tries were hard to come by.
The Brumbies and Waratahs showed some old-fashioned grit as they went toe to toe in a top of the conference contest.
Both teams scored a try in the first half, but it was the goal kickers that decided the game.
Christian Lealiifano missed a crucial penalty attempt from in front in the first half while Kurtley Beale and Bernard Foley booted the Waratahs to a tight win.
It was just their third win in Canberra in 20 seasons of Super Rugby.
"It was a good win, in our time together we hadn't won here in Canberra and we just dogged it out," said Waratahs coach Michael Cheika.
Australian rugby people should be proud of the teams we've got because they put everything on the line tonight.
"We're still putting ourself under some pressure, but the Brumbies came with some hard line speed.
"It was a difficult game to get any control on, we just edged ahead. Sometimes we've got to get over it and get on to the [Wallabies]. The Brumbies are an excellent team and will still be a force in the competition."
In the battle Wallabies No. 7 rivals, Pocock was outstanding at the breakdown and was a constant pest for the Waratahs while Hooper put on some big hits in defence.
Veteran NSW hooker Tatafu Polota-Nau was knocked out in just the second minute, continuing his horror run with concussions and he was forced to leave the field.
Polota-Nau failed to return to the field and there will be doubts over his availability in the coming weeks after missing two weeks to recover from a head knock earlier in the season.
It was the Brumbies landing the big blows first, dominating field position and then stretching the Waratahs' defence to score the first try of the game.
Robbie Coleman floated a long ball wide to Joseph Tomane to open up a seven-point lead, despite some question marks whether the pass was forward.
It did little to rattle the defending champion Waratahs as they held on to the ball for almost 10 minutes to get themselves back in the match.
They were rewarded when their attacking persistence had the Brumbies frazzled and Adam Ashley-Cooper scored in the corner.
The Brumbies had trouble at scrum time but the Waratahs struggled with their handling and in the lineouts as both teams struggled to build any momentum.
The Waratahs blew their last attacking chance of the first half by throwing a forward pass, allowing the Brumbies to hold on to a 10-7 lead at the break.
Tempers started to boil over when they got back on the field with spotfires breaking out everytime players got caught on the bottom of a ruck.
Hooper had blood streaming from a cut on his head and Brumbies flanker Scott Fardy was opened up above his eye as Beale and Foley booted the Waratahs to a 13-10 lead.
"Every time we play the Brumbies it's an absolute grind and we knew we had to be ready for the battle, to get the win is very satisfying," Foley said.
"Defence won it for us, we had our backs to the wall in the second half but the guys stuck strong. It's very satisfying to get a win down here.
"It does give us confidence, we still haven't played the 80 minute performance we'd like but away wins like this are pretty special."
Waratahs winger Rob Horne was sent to the sin bin with 15 minutes to go for a blatantly trying to illegally stop the Brumbies' rolling maul.
But the Brumbies failed to capitalise and the Waratahs held on for a three-point triumph.
AT A GLANCE
NSW WARATAHS 13 (Adam Ashley-Cooper try; Bernard Foley conversion; Kurtley Beale, Bernard Foley penalties) ACT BRUMBIES 10 (Joseph Tomane try; Christian Lealiifano conversion, penalty).
- Canberra Times
