Australia captain Mile Jedinak will miss the Socceroos' crucial upcoming World Cup qualifiers against Japan and Thailand.

The Aston Villa midfielder is nearing a return but has been sidelined since June with a groin injury.

Jedinak was ruled out of Australia's final two third-round qualifiers on Wednesday, with coach Ange Postecoglou unwilling to risk the 33-year-old.

"We wanted to give him every chance and he was very keen to be a part of it," Postecoglou told a news conference.

"But speaking to him, contacting him last night, he was probably not going to get in that game that he needs to see how he feels.

"And with it being a fairly long trip – and with his long absence from game time – probably he felt he wasn't right.

"From that perspective he ruled himself out."

Defender Trent Sainsbury was included in the 23-man squad despite last playing at the Confederations Cup.

Australia are third in Group B – level on points with Saudi Arabia and one adrift of Japan.

The Socceroos face Japan in Saitama on August 31 before hosting Thailand in Melbourne five days later.

Australia:

Goalkeepers: Mitchell Langerak (Stuttgart), Mat Ryan (Brighton and Hove Albion), Danny Vukovic (Genk)

Defenders: Milos Degenek (Yokohama F Marinos), Alex Gersbach (Rosenborg), Ryan McGowan (Al Sharjah), Trent Sainsbury (Jiangsu Suning), Brad Smith (Bournemouth), Matthew Spiranovic (Hangzhou Greentown), Bailey Wright (Bristol City)

Midfielders: Mustafa Amini (Aarhus), Jackson Irvine (Burton Albion), Massimo Luongo (QPR), Mark Milligan (Melbourne Victory), Aaron Mooy (Huddersfield Town), Tom Rogic (Celtic), James Troisi (Melbourne Victory)

Forwards: Tim Cahill (Melbourne City), Tomi Juric (Luzern), Robbie Kruse (Bochum), Mathew Leckie (Hertha Berlin), Awer Mabil (Pacos de Ferreira), Jamie Maclaren (Darmstadt)