FOOTBALL bosses are becoming increasingly concerned by the growing use of 'snus' tobacco pouches among players.

Ex-England star Jamie Vardy has admitted taking smokeless snus in the past to help boost his mental sharpness - even on international duty.

4 The growing use of tobacco pouches is causing concern among football bosses

And now there are fears that a growing number of Premier League players are also seeking the nicotine hits despite the sale of the tins being banned in the UK.

The Mail say use of snus (pronounced snooze) has exploded among young players in England with some even taking them during matches.

Sales of snus in Britain have been illegal since 1992, after they were linked to causing cancer, but they can still be sourced over the internet.

While they are not banned for enhancing performance, snus pouches are on the World Anti-Dpoing Agency's watch-list.

4 Jamie Vardy was spotted carrying a tin of snus while on international duty with England in 2016 Credit: Fame Flynet

Those who place the pouches between their upper lip and gums believe the 27.3mg hit of nicotine helps with their concentration and alertness.

They come in tins of 18 packs, in several flavours including mint, and offer a nicotine hit around three times greater than the 10mg in a cigarette.

Leicester star Vardy has been spotted carrying a tin of Thunder Ultra while on England duty, and admitted to using it in his autobiography.

He wrote: "When I joined Leicester I started using snus, which are nicotine patches that you place against your gums for ten minutes or so.

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"I used to have the odd fag on a night out at Fleetwood, but one of the lads introduced me to snus when I signed for Leicester and I found they helped me chill out.

"A lot more footballers use them than people realise, and some lads even play with them during matches."

The article claims snus debris was discovered in the dugout at the King Power Stadium after a recent Leicester game.

4 Vardy opened up about his use of snus in his autobiography Credit: Fame Flynet

And while there is no suggestion of any wrong-doing, the amount of players turning to the tobacco is causing concern for managers.

One Championship boss is quoted as saying footballers are using it as an appetite suppressant without real knowledge of the potential health risks.

He said: "It's absolutely rife. It's a disaster.

"It gives you a buzz and you've got players putting it in before and during games.

4 Vardy says he was introduced to the use of snus when he joined Leicester Credit: Getty

"Next time you're watching a game, look at how many players look like they have something behind their top lips. That's a tell-tale sign."

The PFA's deputy chief executive John Bramhall admitted: "It is something that we are aware of and will monitor.

"We will be looking to see if there is a need to educate members on the potential risks involved in using this substance."

A Leicester City spokesman said: "Our players comply fully with all anti-doping regulations.

"We offer regular advice on a variety of topics to maintain their health and seek up-to-date research to ensure such advice is well-founded."