Fighting against a mountain of second-half possession and a hostile Brisbane crowd, the Brumbies refused to wilt under almost 40 minutes of constant pressure and intensity to break a two-year Suncorp Stadium hoodoo.

But the Brumbies were facing a nervous overnight wait on hooker Stephen Moore, who lashed out with a swinging arm against Reds' flanker Eddie Quirk in a incident which infuriated Queensland fans.

Tempers almost boiled over in the 49th minute when Quirk held on to Moore at the breakdown as the Reds peppered the Brumbies' line.

Moore retaliated in an attempt to break free, punching Quirk in the stomach as frustrations spilled out.

It fired up the Reds crowd and Quirk, while in the background scrumhalf Will Genia dived over in the corner.

Referee Steve Walsh deemed Quirk was in the wrong for holding on to Moore and overruled Genia's five pointer by returning to an earlier infringement on the opposite side of the field.

Moore escaped on-field punishment despite fans calling for him to be sent off and the Brumbies will find out on Saturday if the Test rake has been cited by the commissioner.

If he's suspended, it would be a major blow to the Brumbies as they prepare for a blockbuster Anzac Day clash against the Waikato Chiefs in Canberra.

The Reds were furious, but the Brumbies backed Walsh's ruling with director of rugby Laurie Fisher declaring SANZAR, Super Rugby's governing body, needed to stamp out holding on at the rucks.

Brumbies captain Ben Mowen described holding on at the rucks as "little crap things in the game".

"[Moore] was being held, which is the first illegality, and he tried to get rid of him and tried to hack his arm off to get rid of him," Fisher said.

"I know there's a strong push to get rid of that in the game and it happened to [Springbok] Schalk Burger a couple of weeks ago.

"The first offence, which ultimately cost the Reds a try, was holding on around the ruck and the sooner they get rid of that the better. The bottom line is you cannot hold a player. I don't get how bad or good it looks, you can't hold a player."

Reds coach Richard Graham was fuming but stopped short of calling for action to be taken against Moore.

Reds fans were so angry they hurled abuse at Walsh and Moore at the end of the game.

"I would say Stephen Moore is part of the breakdown because he's got his hand on the ruck, so therefore I think Ed Quirk is entitled to hold him," Graham said.

"The punch ... you've watched enough football. I think the try should have been awarded. I'll review it once I leave here, there's plenty of discussion going on with the citing commissioner."

Both teams scored two tries and squandered plenty of chances in an open battle.

Scott Frady and Joseph Tomane scored for the Brumbies while Quirk and Beau Robinson got across the line for the Reds.

The loss leaves the Reds' finals hopes dangling by a thread with just three wins from their first eight games, while the Brumbies will hang on to top spot in the Australian conference for at least one more week.

It was also the first time since 2009 the Reds had lost back-to-back games at home.

The Reds clawed their way back from a 13-point deficit in the second half to cut the margin to just three points with time running out.

The Brumbies have now won six of their first eight games and are targeting a top two finish on the ladder.

''It's a really pleasing win. The Reds are a good side, at home, but when they're at home, they're even better,'' Brumbies captain Ben Mowen said.

''I thought the way we defended in the second half was outstanding and really got us a result in the end.

''It's been a long nine-week stretch for us, but we had to dig deep, and I think the team can be pleased.''

The Brumbies scored two first-half tries to set up early dominance, but the Reds scored two of their own from set pieces to close the gap.

The Brumbies missed out on another bonus point, but their outstanding scrambling defence will lay the foundation for a second half of the year charge to the play-offs.

The Brumbies dominated the first half, holding onto 70 per cent of the possession to establish a 20-10 lead.

But the Reds' missed opportunities, including Genia's disallowed try and Cooper dropping the ball over the line, ultimately cost the Queensland any hope of winning.

ACT BRUMBIES 23 (Scott Fardy, Joseph Tomane tries; Nic White 2 conversions, 3 penalties) bt QUEENSLAND REDS 20 (Beau Robinson, Eddie Quirk tries; Quade Cooper 2 conversions, 2 penalties) at Suncorp Stadium on Friday night. Referee: Steve Walsh. Crowd: 30,004.