Milner sat through Villa's 1-0 victory over Bolton on Saturday on the bench after heading into the game as a doubt with an Achilles injury.
Boss Martin O'Neill is convinced the respite will have helped the 24-year-old, and he will now be raring to go for the cup clash.
Raring to go: James Milner (right) in action during the recent 7-1 defeat to Chelsea
O'Neill told the Express & Star: 'I'm pleased we could rest him, because I think it was probably good for him.
'It was pleasing to have won the game without him, and I'm hoping he will recover in time for next Saturday and the rest will do him good.'
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