The Brumbies face a massive challenge against the defending champions, Otago Highlanders, in Invercargill on Saturday as they attempt to break a Kiwi curse that is haunting Australian teams.

The trans-Tasman rivalry has been lopsided this season, with Australian sides winning just two of 12 matches against New Zealand opponents.

The statistics get worse for the Brumbies, who have conceded 88 points in their past two Kiwi battles - 48 against the Waikato Chiefs and 40 against the Canterbury Crusaders.

It hasn't been all bad for the Brumbies against New Zealand teams after they thrashed the Wellington Hurricanes in the first game of the year.

But the defensive figures makes for tough reading for collision coach Ryan, who has ramped up defensive drills in the past two weeks to rebuild the Brumbies' brick wall.

The Brumbies conceded just 21 tries in 16 regular-season games last season. They've already let in 24 tries in just eight games this year.

"I think our defence systems are still pretty good. For example, last week [against the Crusaders] we had four tries come from turnovers," Ryan said.

"I actually think we've improved, and this week is going to be a real test for us because these Highlander guys are red hot. But I don't think there are major issues [with the defence].

"We had a bit of an attitude adjustment last week and I think that will put us in a strong position to not bleed points this weekend. We are in our next cycle of defence work ... I'm going to say we'll improve from here week to week until the end of the season."

The Chiefs and the Crusaders have scored the most tries of any teams in Super Rugby, with 43 and 36, respectively, signalling their title credentials.

Both teams scored six tries each against the Brumbies to rack up record scores at Canberra Stadium.

The Highlanders haven't quite hit top gear yet this season and will be out to make amends for a shock home loss to the Durban Sharks last week.

Making it even tougher is the fact the Brumbies are going to a rugby graveyard for visiting teams at Invercargill in the deep south of New Zealand.

The Highlanders have lost just once in 10 games at the ground since 2003, including inflicting pain on the Brumbies in 2011.

Ryan, a former NRL premiership winner with the Brisbane Broncos and Super Rugby champion with the Brumbies, expected the Highlanders to try to spark their side-to-side attack against the Brumbies.

"Sometimes, the way we defend, we're left open with offloads because we expect guys to be proactive and get forward," Ryan said.

"I don't think we're in a bad way, put it that way. The Highlanders are a little bit [like the Chiefs and Crusaders], they still play sideline to sideline."

The Brumbies are set to make several changes to their side for the match against the Highlanders, with co-captain Stephen Moore battling to overcome a calf injury and winger Joseph Tomane ruled out for up to eight weeks.

Wallabies coach Michael Cheika said the in-form winger could still play a part in the mid-year Test series against England.

"I'd be confident with the injury that we can work hard to get him back for the June series," Cheika said on Wednesday.

SUPER RUGBY ROUND 10

Saturday: Otago Highlanders v ACT Brumbies at Invercargill, New Zealand, 5.35pm. TV time: Live on Fox Sports 2.