First of all he had never met Cheika. Then there was the fact he'd played just seven Super Rugby games, all from the bench, after leaving his life as a carpenter 12 months ago.

But the email was no hoax and a shocked Powell is set to chase his boyhood Wallabies dream as part of a 39-man squad to play against England next month.

Powell was the biggest bolter in Cheika's squad that included 10 Brumbies for the three-Test series against England.

The 22-year-old opted not to show any of his teammates Cheika's email for fear of being the butt of a joke.

But when Brumbies mentor and Wallabies assistant coach Stephen Larkham called him into the office, the news hit home that Powell was being given a chance to earn a Test debut.

The 22-year-old former tradie is so unknown in Super Rugby circles that New Zealand fans resorted last month to calling him "Goldilocks" because they didn't know his name.

"I guess it's sinking in now. I've never even met Michael Cheika so when I was walking back from lunch and I saw the email, I was sure it was just a stitch-up," Powell said.

"Then [Larkham] took my upstairs and he said it must have been a joke as well. But then he came clean and told me ... it was a pretty big rollercoaster. I didn't know what was happening.

"I just thought it was someone making a mistake or having a laugh. Mum and dad didn't even answer when I called them, either.

"It's definitely come out of the blue, I didn't expect it. I haven't even played a full game of Super Rugby ... it's pretty surprising but I'm pretty happy."

Powell might be flying high with his Wallabies news, but he'll start on the bench for the Brumbies against the Japan Sunwolves at Canberra Stadium on Saturday night.

Larkham has made a handful of changes, resting Tomas Cubelli and Ben Alexander which opens the door for Michael Dowsett to start at scrumhalf for the first time this year, Ruan Smith to shift to the front row and Les Leulua'iali'i-Makin to return to the bench.

Cheika named uncapped Brumbies Powell, Rory Arnold and Allan Alaalatoa alongside Test regulars Stephen Moore David Pocock, Scott Sio, Sam Carter, Scott Fardy, Tevita Kuridrani and Christian Lealiifano.

Powell is certainly the most intriguing selection in the group and he follows the path of Brumbies teammate Ben Alexander who was called into the 2008 Wallabies squad after just six Super Rugby games.

Powell leaps over Nick Stirzaker in the pecking order and will compete with Nick Phipps and Nick Frisby for game time against England.

"It doesn't matter if you're playing five minutes or 80 minutes, what you do out there in that space of time has got to be the best you can do," Cheika said.

"I know that he [Powell] hasn't had a lot of minutes, but in the minutes he's had he's looked really good. Sometimes you go with a bit of gut feeling there too.

"I've never even met him … but I like what he's given on the field around pace and his attention to the ruck."

The Brumbies plucked Powell off a Canberra job site last year to throw him into the Super Rugby cauldron and he impressed enough to earn a contract.

The former Australian under-20s No.9 has been a Brumbies member since he was four years old, but even playing Super Rugby was a distant goal a year ago.

"I guess I have to be confident now, I've been given the opportunity so I've got to step up to it," Powell said.

"I've got a lot of growing up to do this week, I've got to concentrate and do the best I can when I'm there so I don't look out of my depth.

"Was Wallabies on my radar last year? Brumbies was barely on my radar. Playing for the Wallabies was just a distant thought, more of a dream than anything. I didn't think it was realistic, but I've got to be ready now."

SUPER RUGBY ROUND 14

Saturday: ACT Brumbies v Japan Sunwolves at Canberra Stadium, 7.45pm. Tickets available from Ticketek. TV time: Live on Fox Sports 2.

Brumbies team: 15. Aidan Toua, 14. Nigel Ah Wong, 13. Tevita Kuridrani, 12. Robbie Coleman, 11. James Dargaville, 10. Christian Lealiifano, 9. Michael Dowsett, 8. Jarrad Butler, 7. David Pocock, 6. Scott Fardy, 5. Sam Carter, 4. Rory Arnold, 3. Ruan Smith, 2. Stephen Moore, 1. Scott Sio. Reserves: 16. Josh Mann-Rea, 17. Allan Alaalatoa, 18. Leslie Leulua'iali'i-Makin, 19. Tom Staniforth, 20. Jordan Smiler, 21. Joe Powell, 22. Jordan Jackson-Hope, 23. Lausii Taliauli.

Wallabies squad: Allan Alaalatoa (Brumbies), Rory Arnold (Brumbies), Sam Carter (Brumbies), Adam Coleman (Western Force), Scott Fardy (Brumbies), Israel Folau (NSW Waratahs), Bernard Foley (NSW Waratahs), Nick Frisby (Queensland Reds), Liam Gill (Queensland Reds), James Hanson (Melbourne Rebels), Mike Harris (Melbourne Rebels), Dane Haylett-Petty (Western Force), Greg Holmes (Queensland Reds), Michael Hooper (NSW Waratahs), Rob Horne (NSW Waratahs), James Horwill (Harlequins), Leroy Houston (Queensland Reds), Karmichael Hunt (Queensland Reds), Sekope Kepu (Bordeaux), Samu Kerevi (Queensland Reds), Tevita Kuridrani (Brumbies), Christian Lealiifano (Brumbies), Ben McCalman (Western Force), Sean McMahon (Melbourne Rebels), Stephen Moore (c) (Brumbies), Luke Morahan (Western Force), Dean Mumm (NSW Waratahs), Eto Nabuli (Queensland Reds), Taqele Naiyaravoro (NSW Waratahs), Wycliff Palu (NSW Waratahs), Nick Phipps (NSW Waratahs), David Pocock (Brumbies), Tatafu Polota-Nau (NSW Waratahs), Joe Powell (Brumbies), Rob Simmons (Queensland Reds), Scott Sio (Brumbies), Will Skelton (NSW Waratahs), James Slipper (Queensland Reds), Toby Smith (Melbourne Rebels).