The west-Queanbeyan side will take plenty to work on into their upcoming match against the Woden Valley Rams in Phillip on Sunday, after suffering their first loss to the West Belconnen Warriors in five years.

Pearce said their defence was terrible and their attack was lazy in the 22-14 result at Freebody Oval, on a day where the reserve grade side also suffered a loss- its first to the Warriors since 2010.

For the first grade side it was their first loss against any side since last season's major semi-final against cross-town rivals the Blues.

Pearce summed up the game by saying "a lot went wrong".

"Our preparation before the game wasn't very good. We didn't have many at training, and we just didn't have our heads in the game," said Pearce.

"We were disorganised that's for sure."

Defence has been the main issue for the Kangaroos so far this season, with their 22 points conceded against the Warriors their second worst effort next to the 28 points they leaked in their draw to the Goulburn Workers Bulldogs in round four.

Pearce said his men gave West Belconnen too many metres in the game and that made it hard defensively to stop them.

"It's an area of our game we really need to work on," he said.

"We got back together on Tuesday night and watched the video, and Aaron told us we were going through the motions too much and hoping things would happen when we didn't try to make them happen."

West Belconnen are no longer the easy-beats they were in the past two seasons, sitting in fourth with four wins and just one point from the top of the table, but Pearce said if his men want to be reckoned with, they should still be putting each other side to the sword.