Rory Best will lead the Lions into their sixth game on tour looking to maintain their 100 per cent record. The Brumbies are the top team in Australia, are coached by the former South African World Cup winning coach Jake White and they can smell blood.
Not only that, they will have revenge in mind after the cruel way in which a famous win over the Lions was snatched from their grasp in the dying seconds of a thrilling match at the same venue 12 years ago. Austin Healey's try and Matt Dawson's conversion saved the Lions on that day as they emerged winners by 30-28.
All the ingredients are there for another nail-biter, especially as the Lions have had to patch up their back division with four recruits. While Billy Twelvetrees, Christian Wade and Brad Barritt will make their Lions debuts, Shane Williams will make the most unlikely return to the international stage at the ripe old age of 36.
For one night only the Welsh try scoring machine has been asked to raise his standards from the Japanese league, where he is currently in the dying embers of one of the great careers, to match the best Super Rugby has to offer. Throw in Stuart Hogg at outside half, and Rob Kearney making his first start on tour at full back, and the Lions back line looks more like a patchwork quilt than anything else.
But head coach Warren Gatland has never been averse to taking a risk, and his gamble on patching up the midweek side ahead of Saturday's first Test in Brisbane makes perfect sense. It is a case of giving players time to recover from injury, not risking others and wrapping in cotton wool the players he needs to tackle the Qantas Wallabies at Suncorp Stadium at the weekend.
He has also set high standards for the team who will be defending his side's unbeaten record in the Australian capital on Tuesday night. They have everything to play for he says.
"If people play well and put their hand up then we expect to have a few selection headaches. We are undefeated at the moment and even if you are playing on Tuesday you won't want to be part of a Lions side that is going pretty well and loses," he said.
"We want to go as long as we can undefeated because then the scalp just becomes bigger and bigger. The players who play on Tuesday will bear the responsibilities of keeping it going.
"They have a chance to put up their hand to be selected for the Test side, but they also have to keep the momentum and morale in the squad going. That's going to be key for us."
Whatever the result on Tuesday night it is not going to derail either the Lions or the Qantas Wallabies. But it might just give the Lions a slight psychological lift if they can make it six from six.
The Brumbies will have full back Jesse Mogg trying to make an impression after he was unfortunate to be left out of the Qantas Wallabies squad and they will have the bulk of the squad that has helped them win the Australian Conference and head into the play-offs of Super Rugby this year.
It would have been a potential banana-skin game in the week of the first Test in any case, but given the Lions injuries it is going to be an even bigger challenge. Only the Crusaders have won in Canberra this season - can the Lions match that achievement?