Press Association Manager Remi Garde said the 20-year-old was “not professional” after he was pictured partying last weekend after Villa’s 4-0 Barclays Premier League defeat to Everton. Grealish has since been training with the Villa under-21 side and will continue to do so, Garde said at a Thursday morning press conference. Aston Villa midfielder Jack Grealish will be left out of the squad for Saturday’s match against Watford as punishment for his off-field behaviour. Garde’s predecessor, Tim Sherwood, warned Grealish about his behaviour after the Tenerife incident telling him that he had to ”knuckle down”, while Garde had already said he felt the winger was not playing at the level he should be. Grealish has struggled for form this season with Villa bottom of the Premier League heading into Saturday’s home game against Watford at Villa Park. Grealish has scored just one goal this season, in the 3-2 defeat at Leicester on September 13, and he has not completed the full 90 minutes of any game since the 2-0 lost at Chelsea on October 17. “He won’t be included in the squad for Watford,” said Garde. “(His actions) are not of the professional standard that I expect from my players. That is why Jack is training in the under-21 team.” ”Sometimes, players in every country ask to stay in the city where we are playing. It is not a problem for me, it can happen once or twice during a season. ”The problem for me was not him not being on the bus. ”He is not playing at the weekend and at this stage, I think that is enough. ”Jack has got a lot of ability but he needs to improve his game and work at it.” This is not the first time that Grealish has breached club discipline. The youngster was pictured earlier this year laid on his back in the street during a holiday in Tenerife, for which he was reprimanded by Aston Villa. He has also been pictured partying in Marbella and seen inhaling nitrous oxide, known as laughing gas or ‘hippy crack’, from a balloon in a photograph taken last year.