New Brumbies mentor Dan McKellar organised a pre-season camp at the AIS to test his players mentally and physically, and then he disappeared at the start of a brutal training session.

The players were confused. But McKellar and his coaching staff were watching from a secret location to see which Brumbies would stand tall and announce themselves as Super Rugby leaders.

"None of the coaches turned up. I had a whiteboard there that said no coaches were coming today," McKellar said.

"It had a list of what had to be completed. It was just seeing how the leaders stood up, and how the group completed a training session or task without any direction.

"Because that's what happens in a game. We're not out on the field, it's up to the players to work together.

"So it made them think about all the little things ... timing the drills, filling up the water bottles. They had to work together as a group."

Brumbies players finished a testing three-day camp on Friday afternoon after a final work out at Duntroon. It was the same place their week started when they completed an intense obstacle course.

McKellar wanted to challenge his players in unusual ways, admitting some endured "enormous frustration" at times across a variety of tasks.

There were military obstacle courses, pool sessions, trivia, jenga matches against injured duo David Pocock and Ben Hyne and auctions for materials.

"It's been more of a mental challenge than anything," McKellar said.

"Certainly there's a physical component. But I didn't want the boys being run into the ground or living off rations ... it was about seeing how they deal with their emotions and how that affects others.

"I wanted to see who would step up and handle different situations and scenarios ... how you handle your emotions at critical times is very relevant to Super Rugby. It's a stressful environment and there's pressure."

The Brumbies will play their first trial game next weekend when they clash against the Melbourne Rebels at Seiffert Oval.

It will be the first chance for first-year coach McKellar to see how his team is coming together after the departure of several players and former mentor Stephen Larkham at the end of last year.

Pocock and Christian Lealiifano arrived back in Canberra earlier this week to complete the squad, but Pocock will miss up to seven matches after having knee surgery.

His absence is a massive blow to the Brumbies' hopes of getting their Super Rugby campaign off to a fast start, but it also opens the door for his replacement contenders to impress in the trials.

Tom Cusack, Rob Valetini, Lachie McCaffrey and Lolo Fakaosilea loom as options to replace Pocock, and all will get a chance to prove themselves in two trials and at the Brisbane 10s.

SUPER RUGBY TRIALS

February 3: ACT Brumbies v Melbourne Rebels at Seiffert Oval, 6pm.

February 10-11: Brisbane 10s at Suncorp Stadium

February 14: ACT Brumbies v Waikato Chiefs at Sunshine Coast Stadium, 8pm (AEDT)