Larkham has just five games left in his Brumbies coaching stint as the Australian rugby champion prepares to step into a fulltime Wallabies assistant's role at the end of the season.

Larkham faces the biggest challenge of his coaching career with the Brumbies in danger of slumping to the equal worst losing streak in the club's history.

But Aidan Toua and skipper Sam Carter backed Larkham to manufacture a form turnaround after four losses in a row, insisting he can lead the team to the finals as a parting gift.

The Brumbies are clinging to top spot in the Australian conference and need to beat the Southern Kings in Port Elizabeth on Sunday morning Australian time to hold on to their lead.

"We haven't spoken about it getting to the end of [Larkham's time at the Brumbies], but he has invested so much of his time over 20-odd years at the Brumbies," Toua said.

"As a coach, in my mind, he's still one of the best around. The analysis he does is very thorough and he gives us solid game plans.

"It has to be on the players a little bit for not really executing those plans as well as what we should be under pressure.

"This season hasn't gone as we would have hoped. But through the luck of the Super Rugby system, we're still very much in it and that's all we're looking at."

The Brumbies will likely announce Larkham's successor when the team returns from its two-game tour, with assistant Dan McKellar considered to be the front-runner for the job.

Carter added: "Steve has been a massive part of the club since it started and this is the last year.

"There have been a few moments in a few games that could have gone a different way and this whole situation would be different.

"We haven't spoken about Bernie's last year as a group yet, but the season is creeping up on us and there are only five games left. It has to be about building on our performance to get a complete result."

Larkham described a three-game block before the mid-season break for international rugby as the most important period of the Brumbies' season.

The Brumbies play the Kings before travelling to Argentina and then back to Canberra for a clash against the Rebels on June 3.

If they can win all of those games they will be in the perfect position to secure a play-off spot for the fifth consecutive year.

But to do that, they will have to break a 210 try-scoring drought which has haunted them for the past month and score their first win in five games.

"We're hoping the tightness of the Australian conference brings the best out of guys," Carter said.

"We started the year pretty well but over the past four matches we've been there in parts, but haven't been the complete package.

"It's not like we've been playing bad footy, it's just we haven't been consistent. We have to draw on the positives that we've created in this time."

The Brumbies have lost six games by seven points or less this year. In most of those games they've had easy chances to kick penalty goals, but first-year captain Carter has opted for an attacking style of chasing tries.

Carter said his captaincy was still evolving and he would weigh up penalty situations on their merit.

"The Kings are a very dangerous and attacking team so it won't be like other South African teams," Carter said.

"If we see an opportunity to take the three points [from a penalty], we will do it. But if there's a better chance to go to the corner [for a try] then we'll do that.

"In the end whatever decision is made shouldn't even matter because we move on to the next job if it doesn't go the way we want it to. That's what we're trying to do this week.

"If we can forget about the result and just play our natural game, I know we'll get a good result."

SUPER RUGBY ROUND 13

Sunday: Southern Kings v ACT Brumbies at Nelson Mandela Bay Stadium, Port Elizabeth, 3.30am (AEST). TV time: Live on Fox Sports 1.

Brumbies team: 15. Tom Banks, 14. Henry Speight, 13. Tevita Kuridrani, 12. Kyle Godwin, 11. Aidan Toua, 10. Wharenui Hawera, 9. Joe Powell, 8. Jordan Smiler, 7. Chris Alcock, 6. Scott Fardy, 5. Sam Carter, 4. Rory Arnold, 3. Allan Alaalatoa, 2. Josh Mann-Rea, 1. Ben Alexander. Reserves: 16. Robbie Abel, 17. Nic Mayhew, 18. Les Leuluaialii-Makin, 19. Blake Enever, 20. Jarrad Butler, 21. De Wet Roos, 22. Andrew Muirhead, 23. Andrew Smith.

Kings team: 15. Chrysander Botha, 14. Alshaun Bock, 13. Berton Klaasen, 12. Luzuko Vulindlum, 11. Makazole Mapimpi, 10. Lionel Cronje, 9. Louis Schreuder, 8. Andisa Ntsila, 7. Tyler Paul, 6. Stefan Willemse, 5. Lubabalo Mtyanda, 4. Irne Herbst, 3. Ross Geldenhuys, 2. Martin Bezuidenhout, 1. Schalk van der Merwe. Reserves: 16. Kurt Haupt, 17. Chris Heiberg, 18. Dayan van der Westhuizen, 19. Mzwanele Zito, 20. Thembelani Bholi, 21. Johan Steyn, 22. Pieter-Steyn de Wet, 23. Nicolaas Hanekom