Mowen will equal Brumbies and Wallabies great George Gregan's record as the club's most capped skipper when he plays his 49th game for the ACT on Friday night.

But even as the Brumbies prepare to farewell 17 players and staff, Mowen said there was no room for sentiment if the team wanted to break a decade-long championship drought.

"Being near enough doesn't get you a piece of silverware," Mowen said.

"This group deserves something substantial for the work we have put in. I honestly believe there is a real opportunity in the next couple of weeks to give ourselves a crack of opening that up.

"Greegs won two championships ... it doesn't matter if you've captained the Brumbies 150 times, if you haven't won a championship then you probably haven't done your role properly.

"I think this group deserves a big piece of silverware to say this is why we made sacrifices. If we don't give ourselves that chance, we'll be disappointed. Making the final isn't a result, we want to win it."

Former Wallabies captain Mowen shocked Australian rugby when he announced in January he was quitting the Brumbies to sign with French club Montpellier.

The 29-year-old has been one of the major driving forces in transforming the Brumbies from a rabble at the end of 2011 to grand finalists in 2013.

The Brumbies need to beat the Western Force at Canberra Stadium to secure their place in the play-offs in back-to-back years for the first time since 2003-04.

A loss will almost certainly end the Brumbies' season, but if they secure a losing bonus point and the Auckland Blues beat the Waikato Chiefs, the ACT could still make the finals.

Brumbies coach Stephen Larkham is banking on his team's "big game" experience to give it an edge in the battle against the Force.

The Brumbies will be bolstered by the return of flyhalf Matt Toomua, hooker Josh Mann-Rea and lock Sam Carter.

Pat McCabe and Joseph Tomane will add valuable depth to the Brumbies' bench as they aim to win a last-round match for the first time since 2007.

"Having those guys coming off the bench can create maybe a little bit of fear in the opposition," Larkham said.

"We're certainly not talking about this being the final game of the season. We are talking about this being the start of our finals campaign.

"We feel as though we're a big game team and this is certainly a big game for us. Every game is like a final in Super Rugby; our preparation is consistent and getting to the finals last year ... that's where we get the benefit from playing big games."

Mowen has spent the past month packing up his Canberra home to prepare for his move to France.

He made his Test debut against the British and Irish Lions last year and was tipped to be part of Australia's World Cup campaign.

Moving to France means he misses out on the chance to play at a World Cup, but Mowen said he was comfortable with his decision to leave Australia.

"Each day I show up at training [at Brumbies] I know it's potentially the last time, but you don't allow yourself too much time to reflect on that because you want to make sure there's more to come. I'm excited," Mowen said.

"I thought I'd play in Australia until the World Cup and have five or six years at the Brumbies.

"There were stages when I missed being in the Wallabies camp ... but I know my priorities are elsewhere and you always return to the point where you're comfortable with your decision."