Crocked midfielder Gavin McCann could return for Aston Villa reserves at his former club Sunderland on Wednesday.
It was thought the 27-year-old would miss the rest of the season after surgery to repair a torn cartilage.
But O'Leary said: "Gavin is progressing nicely and is getting better and he has an outside chance of playing in the reserves this week.
"We need to see how he progresses but it would be great to have him back before the end of the season."
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