Emery gets tough

also attended by up to 70 specially-invited women who agreed to give up their mobile phones before being allowed inside.

However, what appears to be CCTV footage caught Ozil, Lacazette, Guendouzi and Aubameyang clearly the worse for wear as they inhale a gas which, though not illegal, starves the brain of oxygen causing dizziness and hallucinations.

The party started about 11pm and broke up at 4am and the view of the club is that the images are an “embarrassment” rather than a serious disciplinary breach.

Football is no stranger to nitrous oxide. Raheem Sterling was twice photographed using the gas before he joined Manchester City from Liverpool in 2015.

Fellow England star Kyle Walker apologised in 2013 after he was pictured inhaling laughing gas, while more recently, nitrous oxide was at the centre of a party in which Jack Grealish upset hotel guests with his behaviour in 2016.

It would have been a different matter at Arsenal if the events had occurred during the season itself.

But after defeats against Manchester City and Chelsea, a 20-game unbeaten run in all competitions has revitalised a club that appeared to be sliding in the final years under Arsene Wenger.

Undoubtedly a manager as fixated on marginal gains as Emery will be disappointed his players were prepared to impair their performance even days before the start of the season.

And he will have left his players in no doubt yesterday that he does not want to see any repeat in the future.