Will this be the tourists first defeat?
There are defining moments on every tour and you get the feeling that Tuesday in Canberra might be one of those for the 2013 British & Irish Lions.
Rory Best will lead the Lions into their sixth game on tour looking to maintain their 100 percent 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 match 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 flyhalf, and Rob Kearney making his first start on tour at fullback, 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 Wallabies in Brisbane 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 match.
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, it is not going to derail either the Lions or the Wallabies.
But it might just give the Lions a slight psychological lift if they can make it six from six.
The Brumbies will have fullback Jesse Mogg trying to make an impression after he was unfortunate to be left out of the 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?
Players to watch:
For the Brumbies: You don't have to look much further than fullback, where Jesse Mogg will have a big point to prove. Flyhalf Matt Toomua can raise his profile with a good performance, while Peter Kimlin has been 'loaned' to the Brumbies to captain them in a rare match against the Lions. Colby Faingaa, Scott Fardy and Scott Sio are other players who could improve their standing in Australia.
For the British and Irish Lions: Top of this list is the diminutive, but very fleet-footed, Shane Williams. At age 36 you would not expect him to be running around on the international stage, but this one-match cameo could be the script for a fairytale addition to his already impressive story. Players with serious Test claims may include Stuart Hogg at flyhalf, Ben Youngs at scrumhalf, No.8 Toby Faletau, flanks Justin Tipuric and Sean O'Brien, lock Richie Gray, and perhaps even veteran hooker Rory Best - himself a late addition to the tour squad.
Head to head: The real entertainment may well be on the wing - Henry Speight and Clyde Rathbone are two powerful Brutes in the Brumbies jersey, up against two bantams in Christian Wade and Shane Williams in the B&I Lions team. The real story here is two players who have come out of retirement - Rathbone enticed back by Brumbies coach Jake White at the beginning of the season after it appeared a series injuries and other setbacks had ended his playing career, and Williams being brought back for one match after having retired from international rugby two years ago. They can't write this script in Hollywood.
2001: B&I Lions won 30-28, Canberra
Prediction: This will only be the second time that the Brumbies meet the B&I Lions. As Canberra was only established in 1913, the Lions have only appeared in Australia's capital city on three occasions. The outbreak of the First and Second World Wars ensured their first match in Canberra didn't take place until 1950, with that fixture and the one in 1966 having been against New South Wales Country selections. Following the manner of their defeat in 2001, no doubt the Brumbies will be determined to get a 'W' on their honours board. However, it is going to be a tall order, despite the depleted nature of the Lions selection. Nic White, fractured scapula, is one of 12 players missing from Tuesday's selection due to Wallaby call-ups and injury. Yet, the Brumbies still have a realistic chance of an upset. We are going to be bold and prediction the Lions' first defeat on tour - the Brumbies by less than 10 points.
Brumbies: 15 Jesse Mogg, 14 Henry Speight, 13 Tevita Kuridrani, 12 Andrew Smith, 11 Clyde Rathbone, 10 Matt Toomua, 9 Ian Prior, 8 Peter Kimlin (captain), 7 Colby Faingaa, 6 Scott Fardy, 5 Sam Carter, 4 Leon Power, 3 Scott Sio, 2 Siliva Siliva, 1 Ruan Smith.
Replacements: 16 Josh Mann-Rea, 17 Jean-Pierre Smith, 18 Chris Cocca, 19 Etienne Oosthuizen, 20 Jordan Smiler, 21 Mark Swanepoel, 22 Robbie Coleman, 23 Zack Holmes.
British and Irish Lions: 15 Rob Kearney, 14 Christian Wade, 13 Brad Barritt, 12 Billy Twelvetrees, 11 Shane Williams, 10 Stuart Hogg, 9 Ben Youngs, 8 Toby Faletau, 7 Justin Tipuric, 6 Sean O'Brien, 5 Richie Gray, 4 Ian Evans, 3 Matt Stevens, 2 Rory Best (captain), 1 Ryan Grant.
Replacements: 16 Richard Hibbard, 17 Alex Corbisiero, 18 Dan Cole, 19 Geoff Parling, 20 Dan Lydiate, 21 Conor Murray, 22 Owen Farrell, 23 Simon Zebo.
Date: Tuesday, June 18
Venue: Canberra Stadium, Canberra
Kick-off: 19.30 (09.30 GMT; 10.30 UK & Ireland time)
Expected weather: There will be rain, likely to be some isolated showers during the match. The winds will be about 25 km/h in the afternoon and it will be cold. High of 11°C and low of 0°C - with the wind-chill factor taking it well below freezing.
Referee: Jérôme Garces (France)
Assistant referees: Craig Joubert (South Africa), Jaco Peyper (South Africa)
TMO: TBC (New Zealand)
With thanks to lionsrugby.com