The Germany international is set to be sidelined for 10 to 12 weeks after straining ligaments in his left knee during a 2-0 loss to Chelsea at Stamford Bridge earlier this month.
Walcott made his full return to Arsenal training at London Colney on Monday after recovering from his own long-term knee injury which has kept the forward out of action since January.
And Gunners midfielder Wilshere is confident that versatile midfielder Oxlade-Chamberlain or Walcott can fill the void left by their club-record signing.
“Ozil was playing on the left a bit so it probably won’t change much in the centre,” Wilshere told Sky Sports.
“Chambo will get a chance. Theo is coming back as well. Now it might give Theo or Chambo a chance.
“It will be hard for him [Ozil] because he likes football, he has never really had an injury before. He had a slight one last season.
“I am not even sure how long it is, I’ve not been back to the club. It will be difficult for him. But he is naturally quite a fit lad so he will be alright.”
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