Aston Villa striker Emile Heskey faces an anxious wait to find out the extent of his ankle injury, sustained in the second half of their win over Portsmouth.
O'Neill said: "Emile has rocked his ankle. I asked Roddy, my doctor, how it was after the game and he said it was sore and he won't be able to assess it properly until tomorrow morning.
"I just don't know at this minute. It is just really unfortunate."