Mogg has been hit with another injury setback which is set to keep him out of action for at least another month as he recovers from an AC joint problem in his shoulder.

It follows a shoulder reconstruction in October and an ear infection last month which derailed his plans for the season.

But Mogg hopes to be back on the field within the next four weeks and wants to be a part of the Brumbies' charge into the play-offs.

"It is getting frustrating, but there's not much I can do about it. You've got to turn it into a positive somehow so that's what I'm doing," Mogg said.

"At this stage I don't want to risk anything by coming back early, but hopefully I can get back and find a spot in the team somewhere.

"They say bad things come in threes, so hopefully that's it and there's nothing else. My confidence rugby wise is good, I just don't know why my neck and shoulder keep giving way."

Mogg hurt his shoulder while trying to tackle Brumbies teammate Rodney Iona in a club rugby game for Wests last weekend.

Mogg is one of several Brumbies off contract at the end of the season and coach Stephen Larkham says his priority is re-signing the current squad before going into the market for recruits.

Prop Ben Alexander and Robbie Coleman are on the radar while the ARU is waiting for David Pocock to string games together before ramping up negotiations with the former Wallabies skipper.

Canterbury Crusaders scrumhalf Andy Ellis is no longer in contention to fill the spot vacated by Nic White, with the Brumbies still on an international search for a No. 9.

The search still includes South African Fourie du Preez, French No. 9 Frederic Michalak and some more players with international experience as the Brumbies target a world-class replacement.

But big-money contracts in Europe and Japan loom as the big stumbling blocks for replacing White.

Mogg has avoided serious damage, but needs an extended stint on the sideline to make sure the AC joint fully recovers before throwing himself back into Super Rugby.

Larkham is confident Mogg will be ready to make a comeback in time for a two-game tour of South Africa in May.

Mogg played in the round three win against the Melbourne Rebels, but was floored by a mystery ear infection a week later which affected his balance.

"His season has been stop-start and we have to wait at least another month now before we see him back," Larkham said.

"He'll be there for the most important end of the season. We've got a difficult block now of seven games in a row.

"Jesse should be right for the trip to South Africa and then the games after that. It's certainly a frustrating year for him, but that happens at certain stages. He's a very intelligent person and understands he will get his chance this year."

Mogg's goal this year was to rediscover his rugby enjoyment.

"I'm not sure why my body isn't coping at the moment. Football wise I feel really confident, I'm just eager to play," Mogg said.

"It's different to what I've been used to [in Super Rugby]. I'm coming up on eight months in rehab, but I'll stay positive."

SUPER RUGBY ROUND NINE

Friday: Auckland Blues v ACT Brumbies at Eden Park, 5.35pm (AEST). TV time: Live on Fox Sports 2.