Arsenal youngster Dan Crowley has been warned about his lack of professionalism by the manager of his loan club Oxford United.
Crowley, 19, has made 11 appearances for the League One side this season but was left out of Oxford’s 4-1 win over Coventry at the weekend.
U’s boss Michael Appleton, quoted by the Oxford Mail, said the teenager’s head was not “in the right place”.
He added: “There are a couple of issues I want to make sure are addressed in terms of what he does on and off the field.
“He’s a 19-year-old lad who has fantastic ability, but his professionalism at times lets him down.
“He’s had a few issues at Arsenal and Barnsley previously. It’s all a massive learning curve for him.
“Ultimately sometimes when people step out of line you have to put them in their place.”
Crowley was part of Aston Villa’s academy until the age of 16, and was part of the squad for their NextGen Series victory over Chelsea in 2013.
Arsenal had to pay Villa £209,000 after Crowley signed for them and he went on to play 13 times for Barnsley while on loan at the Yorkshire club last season.