* Toulon duo named in forwards-heavy 40-man squad
* Flanker Smith and utility back O'Connor omitted
* Four uncapped players included (Adds details, quotes)
MELBOURNE, July 2 (Reuters) - Australia coach Michael Cheika has welcomed France-based backs Matt Giteau and Drew Mitchell into his 40-man training squad for the Rugby Championship against New Zealand, South Africa and Argentina.
The Toulon team mates became eligible to play for the Wallabies after a rule change earlier this year which allowed overseas-based players with 60 international caps to be selected.
The 32-year-old Giteau, capped 92 times for the Wallabies, was once first-choice flyhalf under former coach Robbie Deans, but he was omitted from the 2011 World Cup squad amid reports of a fall-out with the New Zealander.
He was followed to French giants Toulon by 31-year-old winger Mitchell, who played his last test for the Wallabies against Wales in 2012.
The pair heralded their arrival from Europe on Wednesday by posting a photo of themselves drinking champagne on a plane.
The 34-year-old loose forward George Smith was also eligible under the new selection policy, though ignored by Cheika who named Michael Hooper and David Pocock as the openside flankers.
Scott Fardy and young Melbourne Rebel Sean McMahon were named as the blindside flankers.
Cheika included four uncapped players in Melbourne prop Toby Smith, ACT Brumbies lock Rory Arnold, Queensland Reds centre Samu Kerevi and Fiji-born New South Wales Waratahs winger Taqele Naiyaravoro in his squad named on Thursday.
Winger Nick Cummins and utility back James O'Connor were both omitted from a forwards-heavy squad that signals Cheika still has much to ponder in picking his best pack ahead of the World Cup in England.
The squad will assemble in Queensland state's Sunshine Coast on Sunday for a week-long training camp in preparation for their opening match of the abridged Rugby Championship against the Springboks on July 18.
"We're fortunate enough to see some experience enter the squad from both Super Rugby and overseas," Cheika said in a statement.
"It is important we get them connected to the Wallabies culture as soon as possible.
"We are expecting a pretty physical week ahead in Caloundra, and we will look to shave down the squad closer to test week when we arrive in Brisbane to take on the Springboks."
Forwards: Greg Holmes, Toby Smith, Rory Arnold, James Hanson, James Slipper, Tetera Faulkner, Scott Sio, Sekope Kepu, Stephen Moore, Tatafu Polota-Nau, Rob Simmons, Will Skelton, Luke Jones, Dave Dennis, James Horwill, Dean Mumm, Scott Fardy, Scott Higginbotham, Ben McCalman, Wycliff Palu, Sean McMahon, Michael Hooper, David Pocock
Backs: Nick Phipps, Will Genia, Nic White, Bernard Foley, Quade Cooper, Matt Toomua, Samu Kerevi, Matt Giteau, Kurtley Beale, Tevita Kuridrani, Adam Ashley-Cooper, Drew Mitchell, Rob Horne, Henry Speight, Joe Tomane, Taqele Naiyaravoro, Israel Folau