Everton midfielder Ross Barkley needs more 'consistency' under Ronald Koeman, according to former Toffee Leon Osman.
Barkley, 22, has played in all seven of Everton's league games this season, managing one goal and one assist.
But he was left out of the England squad by former boss Sam Allardyce for the match with Slovakia in October.
"Koeman, the way he is around the club, he won't stand for inconsistency and will make him a better player," Osman told BBC Radio 5 live.
Koeman, who succeeded Roberto Martinez at Goodison Park in the summer, told Barkley to "look at yourself" following his most recent international omission.