Arsenal manager Unai Emery will not throw Mesut Ozil back into the Gunners’ side as his work ethic in training is not sufficient, Charlie Nicholas has claimed.While the former Sevilla and Paris Saint-Germain boss has persistently reiterated his trust in the playmaker, he left the 31-year-old out of the matchday squad for Monday’s 1-0 Premier League loss to Sheffield United.Although a Europa League encounter with Vitoria at the Emirates Stadium on Thursday would seem an ideal opportunity to re-integrate the ex-Real Madrid star into the starting XI, the former striker believes that Ozil is set to be consigned to the sidelines once more. Article continues below Editors’ Picks Ox-rated! Dream night in Genk for Liverpool ace after injury nightmare Messi a man for all Champions League seasons – but will this really be Barcelona’s? Are Chelsea this season’s Ajax? Super-subs Batshuayi & Pulisic show Blues can dare to dream Time for another transfer? Giroud’s Chelsea spell set to end like his Arsenal career It is a situation that Nicholas argues is of the player’s own making.“Will he throw Mesut Ozil into this situation?” the former Scotland international said to Sky Sports. “I think Unai Emery knows Ozil is not training hard enough, so that is why he is not putting him in the team.“He is still there so I would play him.”Emery is expected to make numerous changes for the European clash on Thursday, with the likes of Kieran Tierney and Hector Bellerin poised to come back into the team after injury issues.Ozil, meanwhile, has had no such problems and has been restricted to just 142 minutes of football so far this season, half of which arrived in a 5-0 Carabao Cup win over Nottingham Forest, a fixture in which he was presented with the captain’s armband.His only Premier League outing this term came in an away fixture against Watford, in which he played 71 minutes of a 2-2 draw. Otherwise, he has appeared on the bench only a couple of times. The former Germany star has been a divisive figure throughout his career in England, with an astonishing capacity to create goals for others countered by a work ethic that has been regularly questioned.On Saturday, Martin Keown, the former Arsenal centre-back, branded the player’s situation at the club as “embarrassing” for all parties and suggested that the German needs to “look at himself” to help solve his issues at the Emirates Stadium.