One game, 22 Wallabies and a grand final berth up for grabs - Test coach Ewen McKenzie is salivating at an all-Australian Super Rugby semi-final which has the potential to launch World Cup dreams and be a good omen for Australian rugby.

The ACT Brumbies will play the NSW Waratahs in a blockbuster derby in Sydney on Saturday night with the winner advancing to the championship game next week.

It's the first time two Australian teams have squared off in a final since 2002, the same year the Wallabies last won the Bledisloe Cup against New Zealand.

And regardless of the Brumbies-Waratahs result, McKenzie is already planning to transfer Super Rugby success into the Test arena as the Wallabies begin their road to the World Cup in England next year.

McKenzie named a 32-man Wallabies squad on Wednesday, boasting 11 players each from the Brumbies and Waratahs.

Flying Fijian Henry Speight has been included in the squad, despite not being eligible for selection until September 11, while Ben Alexander (neck) and Joseph Tomane (cheekbone) make their Wallabies comebacks after injuries ruled them out of the three-Test series against France last month.

"There's enough in the derby games for us to get a good idea of mate versus mate," McKenzie said.

"Obviously we want guys still upright at the end of it, but we're looking forward to the contest. The reality is you want your teams performing well against the Kiwi and South African teams ... everyone is doing their bit.

"We'll try to take the positivity of what the Tahs and the Brumbies have done and take that forward with the Wallabies."

The Brumbies will name an unchanged line-up for the knockout match against the Waratahs.

Wallabies squad members Tomane and Pat McCabe are still on the bench with the Brumbies' back line firing in the past two weeks, while Clyde Rathbone is pushing to recover from a hamstring injury.

McKenzie "deliberately" delayed naming his squad until Wednesday when both the Brumbies and the Waratahs had a day away from training to avoid distractions.

The derby match will be the biggest Australian Super Rugby contest since the teams last met in a final 12 years ago.

Coincidentally it was the Waratahs against the Brumbies then as well - which the ACT won 51-10 - and a month later the Wallabies beat the All Blacks to claim the Bledisloe Cup.

This year all four starting props are in the Wallabies squad, Henry Speight is squaring off against Rob Horne, while playmaking combination Matt Toomua and Christian Lealiifano will look to get one over Bernard Foley and Kurtley Beale.

The Waratahs finished the regular season at the top of the ladder with the best attacking and defensive record in the competition.

Since losing to the Waratahs 39-8 four weeks ago, the Brumbies have scored 10 tries in their past two games.

"I don't know if they've [the Brumbies] tweaked their game or not, but they've expressed themselves a little bit differently," McKenzie said.

"They are carrying the ball in different parts of the field, which is a bit different. Maybe it's a change of philosophy, I don't know.

"But it's worked for them on the scoreboard, there's a variety about how they go about it and that's not a bad thing to have. A couple of weeks ago I would have said they're contrasting styles, but they've got a lot of similarities."

Brumbies coach Stephen Larkham said potential Wallabies spots would not be a factor in the derby match.

"There's so much focus on the game that it is just about that, the selections were inevitable and we expected them to be in the team," Larkham said.

"Henry's form warrants selection and the Australian public will fall in love with him. But there will be no thought of the Wallabies for now."

FAREWELL THE BRUMBIES

Thursday: The Brumbies are inviting fans to farewell the team from their University of Canberra base at 12.30pm before they leave for Sydney for their semi-final clash against the NSW Waratahs.