But playmaker and co-captain Christian Lealiifano says the Brumbies won't be afraid to push the attacking boundaries against an unpredictable Force side playing with nothing to lose in the last-round fixture.

The Brumbies have made just one change to their team this week, moving Ruan Smith to start at tighthead prop, Ben Alexander to the bench and leaving superstar David Pocock out of the squad as he continues his recovery from a fractured eye socket.

The Brumbies sit on the cusp of a Super Rugby finals berth for the fourth consecutive season and their path to the play-offs will become clearer when the NSW Waratahs play the Auckland Blues on Friday night.

The result of that match will have a direct impact on what the Brumbies must do against the Force to stay alive in the championship race.

The Force are out of finals contention, have won just two games and sacked their coach last month, but the Brumbies will go into battle at full pace to build playoffs momentum.

The Brumbies made too many errors and handed the Blues easy possession in a disappointing loss last weekend that could have torpedoed them out of finals contention.

The Brumbies backs rarely touched the ball against the Blues, but Lealiifano says they are determined to rectify their mistakes and the Force is in the firing line.

The solution, says Lealiifano, is simplifying their game plan instead of using tricks.

"We spoke about that a little bit of complacency or mistakes can hurt you," Lealiifano said.

"Whether that be on the field or in your preparation. We feel like it's a second chance and we've woken up again to push forward now.

"If anything we've probably simplified [the preparation] a bit more so that we can concentrate on the individuals using the skills rather than clouding our minds with tricks and plays.

"To simplify it and know we've got a strong platform there with what our strengths are, and then push the boundaries in attack and things like that.

Brumbies coach Stephen Larkham opted to make minimal changes to the side that lost to the Blues last weekend, putting faith in his players to resurrect their season.

Prop Smith will start in his 50th Super Rugby game with veteran front-rower Alexander shifting to the bench after signing a one-year contract extension.

Pocock hasn't been named in the team as he eases his way back from a fractured eye socket, while Scott Fardy will take his place in the starting side despite bumps and bruises from last week.

Pocock and Jordan Smiler have returned to training but are not ready to be thrown back into Super Rugby.

Lock Sam Carter conceded the Brumbies were "flimsy" in defence in a 40-15 defeat at the hands of the Blues.

"We need to get out there and have a real go," Carter said.

"If we're being serious about the competition and wanting to be in the finals, these are the games we must win and last week wasn't good enough by our standards.

"We want to change that this week. It's a mentality, all the boys need to just go out there and rip in ... but we know the Force are dangerous and whenever they're playing they're always in the contest.

"If we're thinking [about the Waratahs-Blues game] at this stage of the season then we don't deserve to be in the finals.

"We've got a pretty strong mindset. Regardless of the result [in the Waratahs' game], we want to put in a good performance on Saturday."

The Brumbies have scored more than 10 tries from rolling mauls this year and the set move has been the team's go-to play when they're close to the try line.

That has limited the impact of a star-studded back-line, but Carter says the Brumbies will persist with the rolling maul given it has delivered results.

"We get the call from the backs and if we're told to execute the maul, that's what we do," Carter said.

"I think we've scored 10 or 12 maul tries in the season ... if you do it well on the night then it's a chance of success."

SUPER RUGBY ROUND 17

Saturday: ACT Brumbies v Western Force at Canberra Stadium, 7.45pm. Tickets available from Ticketek.

Brumbies team: 15. Aidan Toua, 14. Nigel Ah Wong, 13. Tevita Kuridrani, 12. Matt Toomua, 11. James Dargaville, 10. Christian Lealiifano, 9. Tomas Cubelli, 8 Michael Wells, 7. Jarrad Butler, 6. Scott Fardy, 5. Sam Carter, 4. Rory Arnold, 3. Ruan Smith, 2. Stephen Moore, 1. Scott Sio. Reserves: 16. Josh Mann-Rea, 17. Allan Alaalatoa, 18. Ben Alexander, 19. Blake Enever, 20. Tom Staniforth, 21. Joe Powell, 22. Andrew Smith, 23. Lausii Taliauli.

BRUMBIES FINALS SCENARIOS