O'Neill told the club website: "I'm very optimistic about it because he came in on Sunday and by Monday he felt a million times better. So hopefully he'll be available.
"He wants to play and he understands that sometimes you just get on with it. He's prepared to do that and feels very positive about playing on Saturday.
"John is a very important player for us and we're trying to use his experience to help the younger players alongside him - Gabby (Agbonlahor), Ashley Young and Shaun Maloney."