Aston Villa manager Tim Sherwood says the club does not condone reported behavior involving youngster Jack Grealish.

An image of Grealish inhaling nitrous oxide emerged in The Sun on Thursday in what is the latest of a series of young players partaking in the use of the laughing gas.

The picture is believed to be a year old but Sherwood still feels that a talented player like Grealish does not need to be getting involved in such off-field mischiefs.

"I spoke to Jack when he came in first thing this morning and explained this kind of behaviour can't be tolerated by the football club," he said.

"We can't condone that behaviour. He is a young man, and he was even younger when that photo was taken, but it doesn't matter.

"He's in a responsible position as a professional footballer but he's assured me that it won't happen again.

"I'm not worried about him. There's only one form of discipline and that's self-discipline. Jack needs to take that on board and it's an eye-opener for him. He's got to be careful who he trusts out there."