Michael Cheika has named 17 forwards and 14 backs in his 31-man Wallabies Rugby World Cup squad, the playing roster boasting more than 1200 Test caps.

Toby Smith and Sean McMahon are the only players named in the squad who have not featured during the 2015 international season, the pair selected to offer a more balanced and versatile back-row and props group.

Cheika said the collective effort of his broader Wallabies playing group had laid the platform for his chosen squad to lead Australia against the rest of the world.

"Firstly, I would like to thank all of the players who have contributed to the Wallabies' Rugby Championship and Bledisloe Cup campaigns this season," Cheika said. "We've become a really tight group and it was a very difficult process in picking only 31 players, but I know each player selected will travel to England with the full support of those team mates who won't board the flight.

"Our primary focus throughout the Super Rugby competition, The Rugby Championship and Bledisloe Cup was to select a balanced squad between youth, experience and form and this squad certainly delivers on this. It's also important that we select a squad that will handle the tournament play and our draw in particular at the Rugby World Cup, as well as maintain a strong competition for places in the team."

Cheika explained the rationale for the balance between backs and forwards, and the identity of the players, by saying "we focused pretty much on having two clean teams plus an extra front-rower".

"We've pretty much got two starting XVs there; the nature of our pool that's something we wanted to have - having two fresh teams and the ability to train against each other with quality and managing our pool, in tournament-type play."

Cheika is pleased with the team's progress since he assumed the Wallabies' reins in October 2014, but he is adamant his charges will lift another gear for the Rugby World Cup.

"The first part of the year during the Super Rugby Season, we worked hard at building relationships and strong foundations, and during The Rugby Championship we wanted to continue to improve and play a brand of rugby that Australia could be proud of and get every player contributing towards the outcome," he said.

"It's essential that we continue to improve over the next four weeks as a squad and we'll be working hard to make sure we deliver on the qualities we want people to see in the Wallabies team of 2015."

Cheika has also named 10 players in an extended Wallabies Squad to face the United States Eagles at Soldier Field, Chicago, September 5

"We've selected a wider training squad including an extra 10 players who will train alongside the squad prior to our departure from the USA to England," Cheika said. "Like they've done all year, these players will play a huge role in the team's preparation. We have a great opportunity in the coming month to work hard and make some gains before we take on a very impressive USA outfit ahead of our opening World Cup match against Fiji."

The Wallabies will commence their preparations with a series of camps in Sydney, Indiana and Bath.

Wallabies' Rugby World Cup Squad

Hookers

• Stephen Moore - C (96 Tests)
• Tatafu Polota-Nau (53 Tests)

Props

• Greg Holmes (17 Tests)
• Sekope Kepu (56 Tests)
• Scott Sio (9 Tests)*
• James Slipper (66 Tests)
• Toby Smith (uncapped)*

Locks

• Kane Douglas (15 Tests)*
• Dean Mumm (36 Tests)
• Rob Simmons (52 Tests)
• Will Skelton (11 Tests)*

Back-row

• Michael Hooper (Vice-Captain, 45 Tests)*
• Ben McCalman (40 Tests)
• Sean McMahon (3 Tests)*
• Wycliff Palu (55 Tests)
• David Pocock (50 Tests)
• Scott Fardy (24 Tests)*

Half-backs

• Will Genia (59 Tests)
• Nick Phipps (31 Tests)

Fly-halfs

• Quade Cooper (55 Tests)
• Bernard Foley (17 Tests)*

Inside backs

• Kurtley Beale (52 Tests)
• Matt Giteau (95 Tests)
• Matt Toomua (25 Tests)*

Outside backs

• Adam Ashley-Cooper (Vice-Captain, 108 Tests)
• Israel Folau (33 Tests)*
• Rob Horne (26 Tests)
• Drew Mitchell (65 Tests)
• Henry Speight (3 Tests)*
• Joe Tomane (15 Tests)*
• Tevita Kuridrani (24 Tests)*

*denotes uncapped at a Rugby World Cup

Extended Wallabies squad to play USA Eagles Test at Soldier Field, Chicago, September 5: Sam Carter, David Dennis, Tetera Faulkner, James Hanson, Scott Higginbotham, James Horwill, Samu Kerevi, Christian Leali'ifano, Taqele Naiyaravoro, Nic White.

Here is the @Wallabies squad for @rugbyworldcup - good enough to win it? pic.twitter.com/UiuBZVPDsL

— ESPN Scrum.com (@espnscrum) August 21, 2015