Despite having less than 24 hours to rectify the issue before the Canberra Raiders hosted the Parramatta Eels on Sunday night, stadium ground staff successfully fixed the goal post the morning of the NRL clash.

The northern crossbar was uneven during the Brumbies' 40-16 victory over the NSW Waratahs on Saturday night and it didn't go unnoticed by fans, with some people mocking the issue on social media.

The mishap continues a spate of problems with the ageing Canberra Stadium, with a foul "stench" permeating through the bowels of the venue during the Raiders' round two win over the Wests Tigers.

The uneven crossbar did not cause any issues for the Brumbies' game, but there was urgency to fix the problem before the NRL game on Sunday.

ACT coach Stephen Larkham said after his side's win that he hopes the issue would be investigated to ensure it doesn't happen again.

"There must be some issue with the foundation of the goal post," he said. "We'll investigate that."

The uneven crossbar wasn't the only stadium flaw to rear its head on Saturday night, with Brumbies fans rushing for cover as heavy rain fell throughout the first half.

With only 15 per cent of seats providing protection from the rain, many of the 8018 in attendance were dripping with water by half-time.

The Brumbies have long called for a roof to be included in plans for a new stadium, however ACT Chief Minister Andrew Barr has taken it off the table.

Larkham was pleased his team put on a show for the fans who braved the conditions and hopes a big crowd will turn out for the team's next home game against the Hurricanes at 2.30 on Saturday April 27.

"It was tough for the crowd, particularly in the bowl area," he said. "It's a great atmosphere when the weather is good. We've been chasing bigger crowd numbers for a long time now and the people that come out on nights like this are certainly very much appreciated.

"We've spoken about how a big crowd can lift the confidence of the players, create a great atmosphere and we play better rugby and I think we saw a bit of that in the second half."

The Brumbies have hailed veteran prop James Slipper as a legend of Australian rugby after he became the country's most capped Super Rugby player in the victory.

The 34-year-old made his 178th appearance in the competition, eclipsing former ACT skipper Stephen Moore on top of the leaderboard.

Slipper played 104 game for the Queensland Reds before moving to Canberra in 2019 for a fresh start.

The move triggered the beginning of a remarkable second act, with Slipper continuing to play at a high level and one of Australia's best props.

Both sides were full of praise for the prop, with NSW captain Jake Gordon congratulating him for his contribution to the sport.

"It's a pretty incredible achievement," Gordon said. "He's a great rugby man. I've played him quite a lot and spent time with him in Wallaby camp and he's a good man.

"He's really good for the younger guys, he spent a lot of time with the younger props in Wallabies camp and his leadership is incredible.

"He's captained at international level and he's a great loosehead prop and a great man too."