Real Betis game was 30th July. McCarthy played an hour in that game before being replaced. He then played 66 minutes in Wayne Rooney's testimonial and was only introduced as a sub in the 63rd minute of the game against Espanyol.
What is O'Neill actually saying? That he played for Everton eleven days after the France game or that he played for Everton eleven days after returning to the club post Euros? I presume the latter.
He seems to be clutching at straws a bit (at best, or just completely wrong) even if I kind of enjoyed the overall sentiment of his statement.