David Pocock faces a potential suspension for an alleged neck grab in the Brumbies' biggest ever loss at home to Super Rugby frontrunners the Chiefs.
The superstar flanker was cited by SANZAAR for foul play on rival No.8 Michael Lietch at a maul late in Saturday night's 48-23 defeat at GIO Stadium.
The incident went unpunished by referee Angus Gardner but the governing body's citing commissioner believed it met the red-card threshold and was contrary to good sportsmanship.
Pocock must now front a judicial officer hearing where his fate will be determined.
The news, delivered early Sunday morning, compounded what was a historic loss for the Australian conference leaders.
It was the club's largest ever losing margin in Canberra; eclipsing their 33-15 loss to the Hurricanes in 2008 and 41-23 defeat to the Sharks in 1998.
And not since 2011 have they conceded as many points in a match.
But coach Stephen Larkham said effort, not results, was what mattered most.
"And I think there was plenty of effort out there," he said.
"There's obviously areas that we need to work on.
"Defensively, around the halfway mark was an area we got found out (but) our defensive effort on our line was superb and I think that's what's been a hallmark of this team for a number of years."
The hosts were up 6-0 after 10 minutes and 13-12 moments before half-time, but a red-hot Chiefs outfit proved too much - running in six tries to two, including a double to winger James Lowe.
Very poor TMO work - ref identifies the neck problem on Chiefs No 8, which is clearly visible due to Pocock utilizing neck lock. V dangerous— Andrew Campbell (@ADC_CapeTown) April 2, 2016
The Brumbies have a much-needed bye next week to recover from a tough month on the road to Perth and South Africa, before they face the NSW Waratahs in Sydney on April 16.
Several players will attend a Wallabies camp over coming days while others go on community visits, before they get some time off and regather for training Monday week.
"It's a well-earned break to get away from rugby and then come back nice and fresh," Larkham said.
"I think that will be our first standard week this year, in terms of seven-day turnaround, so it'll be good to get back into rugby and our usual cycle."
Co-captain Stephen Moore is hoping the break will give his injured teammates time to recover, namely Blake Enever, Jarrod Butler and Henry Speight.
"We've got to take stock, we've had a big six weeks but there's a long way to go so we've got to dust ourselves off and go again," he said.
BRUMBIES BIGGEST HOME LOSSES
25 points (48-23): v Chiefs, round 6 2016
18 points (33-15): v Hurricanes, round 5 2008
18 points (41-23): v Sharks, round 3 1998
14 points (30-16): v Blues, round 18 2012
14 points (42-28): v Chiefs, round 8 2008
13 points (37-24): v Crusaders, round 18 2015
13 points (16-3): v Stormers, round 15 2011