"The African Nations Cup is coming up and I do think players think about it," McCarthy told the Wolves website.
"He has admitted that he hasn't been at his best recently and he is a player that sets high standards for himself.
"He's allowed the odd bad one but when you add that to the loss of Jody Craddock and Michael Kightly, it doesn't do you any favours."
"The last 30 minutes on Saturday was the best Seyi's played for the last few games."