Socceroos skipper Lucas Neill's suspension could open the door for A-League duo Michael Thwaite and Jade North to press their 2014 World Cup claims in the vital qualifier against Oman.
Perth Glory's fit-again Thwaite and Brisbane Roar's North are among the leading candidates to partner Robert Cornthwaite in central defence for the Sydney match on March 26.
Coach Holger Osieck will name his squad on Wednesday for the Stadium Australia clash.
While Middlesbrough's Rhys Williams appears the most obvious choice to slot in for the suspended Neill, the A-League offers plenty of alternatives for Osieck should he wish to see players in the heat of battle.
Thwaite started the Socceroos' 2-1 friendly win over South Korea in November, and has been in excellent form since recovering from a mid-season calf injury.
North has settled in superbly at the Roar since signing mid-season from Japan.
He has been a Socceroos squad regular for the past eight years, though his caps have been spaced and he missed selection for both the 2006 and 2010 World Cup finals.
China-based Ryan McGowan and Melbourne Victory's versatile Mark Milligan can also slot in.
Along with Neill's absence because of exceeding his yellow card limit, another key centre-back option Matthew Spiranovic is understood to be carrying an injury.
He is unlikely to be named in the squad on Wednesday.
With no A-League break for the Oman match, Osieck's selection of domestic-based players could cause headaches for those involved in final-defining fixtures the previous weekend.
Defeat or a draw against Oman could leave Australia in a difficult situation and relying on the generosity of others to qualify for Brazil.
Japan are runaway leaders in the Socceroos' Group B, with Australia having four matches to play.
Australia, Oman, Iraq and Jordan are locked in a close contest for the second automatic qualification spot.
The Socceroos head Oman and Iraq on goal difference, with Jordan a point behind.
A difficult trip to Japan on June 4 follows the Oman clash and could decide Australia's fate, with home matches to round off the qualification campaign against Jordan and Iraq.