While the German coach said Langerak would make his international debut on Sept. 7, he was comfortable with Schwarzer's position at Stamford Bridge, where the 40-year-old stands behind Petr Cech in the pecking order.
Schwarzer, who has won 108 caps for his country, made the short move up Fulham Road after five year as first choice at Craven Cottage during the close season but has yet to make his competitive debut for the former European champions.
"The season is still very young in England and there are many competitions," Osieck said in a teleconference.
"He will get enough playing time. I have discussed it with Mark and with (Chelsea manager) Jose Mourinho, of course."
Osieck said it was "a little bit too early" to say whether Schwarzer would be first choice at the World Cup finals next year or even whether he would start ahead of Langerak in Brasilia next month.
Australia qualified for their third successive World Cup finals, and fourth in total, with a 1-0 victory over Iraq at Sydney's Olympic Stadium in June.
With a friendly against France in Paris coming up in October after the trip to Brazil, Osieck said the squad he named on Wednesday was in no way a reliable blueprint for his World Cup party.
"No, definitely not," he added. "I am still in the phase of trying to find out who can perform for us.
"We have this series of test matches and after this sequence of matches, I will make up my mind. Plenty of other players will get a chance.
"We have Brazil now and then we play France so we have very good opposition. That gives you a good idea of who can perform efficiently at this level."
Middlesbrough defender Rhys Williams might get his chance to shine in Brazil after missing the World Cup qualifiers in June, while domestically-based Mitchell Duke was a surprise call-up.
The Central Coast Mariners striker, who had a trial at West Ham United earlier this month, won his place with some bright performances in an inexperienced Socceroos side which competed at the East Asian Cup last month.
"Mitch played very well in Korea," Osieck said. "Whether he is going to play is another matter but to give him a taste of international football will be a very good experience for him."
- Sports & Recreation
- Mitchell Langerak