The Allianz Arena in Munich will play host to the Group C encounter, as Germany hope to continue their unbeaten record in qualifying.
Joachim Low's side have won five of their six fixtures in the group and top the standings with 16 points.
But they will be more focused on Friday's game against their traditional rivals first, a nation they have an excellent record against.
"I think they will be two really important games," the Real Madrid man said.
"They can help us get our ticket for the World Cup. We have a week ahead of us, where we can practise more intensely and find ourselves. We are fitter and mentally fresh."
Much focus will be on attacking midfielder Mesut Ozil, who joined Arsenal on transfer deadline day from Real Madrid for a reported fee of £42.5million.
Ozil's arrival at the Emirates Stadium has been the subject of much discussion, with several of Real team-mates, including Khedira, voicing their displeasure at his departure.
Low will also have concerns about his side's defence, having conceded nine goals in three friendlies through May, June and August.
They won just one of those fixtures and lost 4-3 to the United States, with Low sure to have spent plenty of time with his defenders on the training pitch in the build-up to Friday's fixture.
Alaba is one of nine German-based players in the Austria squad and they will be quietly hopeful of pulling off an upset after running Low's men close in the reverse fixture.
Germany won 2-1 in Vienna last September thanks to goals from Marco Reus and Ozil.
