Get an experienced player to tutor him. That should help. Also he may no longer be a wonderkid because of his age after about 20 I think it is a good young player is no longer classed as a wonderkid.
1000+ minutes a year? Is that enough? He's not good enough to start regularly so I have to rotate him.Are you playing him regular enough? If not send him out on loan to a good team with good training facilities.