The young Irish international lined up for the Latics in the 4-0 win over Barnsley despite being the subject of much transfer speculation.
New Latics boss Coyle has been noticably impressed by McCarthy's professionalism over what must have been a dififcult summer of transfer rumours.
It is still not clear if McCarthy's future remains with the Latics as the transfer window still has over three weeks to run, but Owen Coyle issued a marked 'hands-off' to Everton.
Speaking after the Barnsley game Coyle said he would be willing to let McCarthy leave for a Champions League club which is likely to be Tottenham (once the Gareth Bale money is received).
The former Botlon and Burnley boss said: "It was difficult for James in the summer. Everyone James met said, 'Which club are you going to?'
"He's a fantastic player and a fantastic human being. His head was all over the place.
"I've said to James that if a Champions League club comes in for him - and he's that good he can play for anyone in that top six - I won't stand in his way.
"I don't want to dismantle the squad but equally there's a moral obligation to do right by the kid. He's been fantastic for Wigan. But we don't have to sell anybody."
The news will be a blow to Roberto Martinez who has spent much of the summer counting the copper in the Everton bank account and raiding the Latics with whatever he could find.
Unless either Baines or Fellaini leave Goodison Park it is unlikely that Everton have the funds to acquire McCarthy and if he is to leave Tottenham or Arsenal are the likely destination.
Officially the Latics are asking for upwards of £20 million but unoffficialy it is rumoured that £15 million will be enough should Spurs be willing to loan the Latics Scott Parker in return for the season.