The Brumbies secured their place in week two of the play-offs when they beat the two-time defending champions the Waikato Chiefs 32-30 in a thrilling match at Canberra Stadium.

And the win, which Brumbies captain Ben Mowen described as the best of the past three years, sets up a mouthwatering contest against the minor premier Waratahs at Allianz Stadium.

Just three weeks ago the Brumbies were embarrassed by a rampaging Waratahs side in Sydney which almost knocked them out of the title race.

But Mowen, the most-capped skipper in Brumbies history, insists the ACT side can improve on its courageous and epic eight-try win which ended the Chiefs' two-year reign as Super Rugby champions.

Beating the Chiefs was sweet revenge for last season's grand final defeat, with the Brumbies withstanding a late surge to hold on for one of the most thrilling wins of the season.

The finals contest will go down as an absolute classic, both teams showing brilliant attacking rugby with brutal defence.

"Without doing a lot of analysis, I have a feeling that's our best performance of the last three years," Mowen said.

"To get that sort of when against that quality of opposition, with the ups and downs of the games ... it was see-sawing and there were one or two moments that if it was the same side of ours four weeks ago, we may have just played conservatively.

"But we put skill in the game ... it's an outstanding win, one of the best of the last three years."

Both teams scored four tries in an absorbing contest.

The Brumbies opened the Chiefs up early, scoring two tries when Tim Nanai-Williams was sent to the sin bin after just five minutes.

The Brumbies led for the entire contest, except for when Aaron Cruden slotted a third-minute penalty goal and when Gareth Anscombe scored match-levelling try with 20 minutes to go.

The Chiefs charged back into the contest in the second half with three superb tries as they attempted to keep their bid for a hat-trick of titles alive.

But Cruden missed a sideline conversion and the Brumbies held on to possession for the last five minutes to clinch victory.

"We played some wonderful football, but in the end it was a bit of grit that got us the win," said Brumbies director of rugby Laurie Fisher.

"It got fairly tense there for a while, it was two sides giving their best. It was a sensational game and if you paid to get in you got your money's worth."

The Brumbies are confident their squad got through the match unscathed as they prepare for a potential blockbuster against the Waratahs.

Sam Carter injured his ankle in the warm-up, but powered through in an inspirational effort.

"He never whinges, he just gets on with it," Mowen said.

Leon Power got a head knock, Jesse Mogg hurt his back and third-string hooker Josh Mann-Rea looked to be nursing a hamstring strain.

Henry Speight feared he had broken his jaw again just before half-time, but the flying Fijian delivered another breathtaking performance which prompted Chiefs coach Dave Rennie to declare the winger ready for Test rugby.

"Hell yeah [he's ready for Test rugby], I think he's been ready for a while," Rennie said.

Referee Craig Joubert almost sent the Brumbies into a riot with line-ball calls going against the home side in the dying stages with the match up for grabs.

He sin-binned Nanai-Williams in the first half for a cynical infringement at the breakdown and then returned the favour by sending crowd-favourite Speight to the sin bin for the same offence.

Both teams scored two tries while the opposition had respective players in the sin bin.

But the boos from Brumbies fans did little to deter the Chiefs, who charged back into the match with a 77th-minute try to replacement Anscombe to get the defending champions within two points.

Cruden's sideline conversion attempt sailed wide, setting up a grandstand finish in the last three minutes.

Brumbies kicker Christian Lealiifano missed two late crucial penalties which left the door open for the Chiefs to snatch victory, but the Brumbies showed enormous courage to hold on.

"We started slowly and gave the Brumbies too big of a lead. We showed a lot of character, but in playoff games you need to be clinical for 80 minutes," said Chiefs co-captain Cruden.

"We are proud to be here, but we really thought we could push on... it wasn't to be."

NBA star Patrick Mills dropped in on Brumbies training on Friday and told the players to use the pain from last year to motivate them on their pursuit of this season's championship.

Now the Brumbies are just one win away from another grand final berth, but must first face the Waratahs or competition powerhouse the Canterbury Crusaders.

"It would be massive for Australian rugby [if we play the Waratahs]. Two in-form sides going up against each other, we're a game apiece so you get a decider and it would be guaranteed an Australian team in the final," Mowen said.

"There's plenty on the table, from our point-of-view we want to go up and spoil it."

ACT BRUMBIES 32 (Nic White, Robbie Coleman, Jesse Mogg, Jarrad Butler tries; Christian Lealiifano 3 conversions, 3 penalties) bt WAIKATO CHIEFS 30 (Bundee Aki, Tawera Kerr-Barlow, Tim Nanai-Williams, Gareth Anscombe tries; Aaron Cruden 2 conversions, 2 penaltlies) at Canberra Stadium on Saturday night. Referee: Craig Joubert. Crowd: 14,284.