Arsene Wenger admitted that he did not know about Mesut Özil’s angry reaction to a drugs test request in the aftermath of Arsenal’s north London derby defeat by Tottenham last weekend, but refused to condemn the midfielder despite him damaging the White Hart Lane changing room.

28-year-old Özil endured a poor afternoon as he was kept quiet by a much better Spurs side, who were able to record a deserved 2-0 victory thanks to goals from Dele Alli and Harry Kane. With tensions already raised between Özil and Arsenal fans given his refusal so far to sign a new contract as he nears his final year with the club, his recent performances have not gone down well with supporters, who believe that the World Cup winner is not giving his all for the club.

But it was revealed this week that Özil’s frustrations got the better of him when he was asked to carry out a random drugs test immediately after the north London derby, and the Germany international initially refused to complete it, before kicking a door and leaving stud marks imprinted on it when he was told to do the test or face a fine.

Despite the incident being widely reported as early as Tuesday evening, Wenger insists he had no idea about it until Friday morning, just before he faced the media ahead of this weekend’s Premier league with Manchester United.

“I am sorry that he kicked the door,” Wenger said. “I don’t think his frustration was towards the drug test, it was towards the game.”

Wenger did confirm though that he will speak with Özil before Sunday’s match with United.

Tottenham vs Arsenal player ratings Show all 23 1 /23 Tottenham vs Arsenal player ratings Tottenham vs Arsenal player ratings Player ratings We run the rule over the two teams after Tottenham's derby victory. Getty Tottenham vs Arsenal player ratings Hugo Lloris - 7 Rarely called into action but on those occasions when he was tested he held his nerve to keep Arsenal out. Getty Images Tottenham vs Arsenal player ratings Kieran Trippier - 6 Not his best of performances. Made a hash of a number of crosses and was quiet at times. Some of his tackling was impressive, though. Tottenham Hotspur FC via Getty I Tottenham vs Arsenal player ratings Toby Alderweireld - 7 Defensively solid both in the air and on the deck. Rarely gifted Arsenal's front men the space or time to trouble the Tottenham goal. AFP/Getty Images Tottenham vs Arsenal player ratings Jan Vertonghen - 8 Tested Cech on a number of occasions with some sharp shooting. A real threat at corners. Fierce at the back. Excellent defensive display. Tottenham Hotspur FC via Getty I Tottenham vs Arsenal player ratings Ben Davies - 7 Hit the ground running and provided Spurs with a real sense of danger down the left flank. Tottenham Hotspur FC via Getty I Tottenham vs Arsenal player ratings Eric Dier - 7 An assured and rounded performance. Kept the Tottenham midfield ticking over all game long. AFP/Getty Images Tottenham vs Arsenal player ratings Victor Wanyama - 8 A true warrior at times. Seemed to emerge victorious from all of his challenges and was brilliant at dictating the tempo of Tottenham's game. Getty Images Tottenham vs Arsenal player ratings Christian Eriksen - 7 Provided the magic to open up Arsenal for Tottenham's first. Particularly dangerous in the visitors' final third. Passing was on point. Tottenham Hotspur FC via Getty I Tottenham vs Arsenal player ratings Dele Alli - 8 Showed real desire and fight for the first goal. An absolute menace across the entire front line for Tottenham. Very rounded performance. AFP/Getty Images Tottenham vs Arsenal player ratings Son Heung-min - 7 Was moved back into his preferred position and looked all the better for it. Enjoyed some piercing runs early on. Tottenham Hotspur FC via Getty I Tottenham vs Arsenal player ratings Harry Kane - 7 Excellent penalty to double Arsenal's lead. Hard working and tireless in his movement. Getty Images Tottenham vs Arsenal player ratings Petr Cech - 7 out of 10 Was tested by a number of challenging shots in the first half and put in some fantastic saves late on to limit the damage. One of the best shot-stoppers in the league. Would have been more were it not for him. Tottenham Hotspur FC via Getty I Tottenham vs Arsenal player ratings Gabriel - 5 A disappointing and uninspiring performance from him. His reckless challenge handed Spurs their second goal after Kane converted from the spot. Getty Images Tottenham vs Arsenal player ratings Laurent Koscielny - 6 Was off the pace for Tottenham's first. Should have moved quicker to close down Alli. Up until then he'd battled relatively well with the home side's front line. Tottenham Hotspur FC via Getty I Tottenham vs Arsenal player ratings Nacho Monreal - 4 Outclassed for much of the game. A considerable chink in Arsenal's weak armour. Getty Images Tottenham vs Arsenal player ratings Alex Oxlade-Chamberlain - 5 Out of his depth. Defensively poor and offered little going forward. Tottenham Hotspur FC via Getty I Tottenham vs Arsenal player ratings Aaron Ramsey - 6 Got a grasp of the game as it wore on and was one of the few Arsenal players to really test Lloris. Drifted out of the game though. Getty Images Tottenham vs Arsenal player ratings Granit Xhaka - 5 Made some solid challenges here and there but largely directionless in his play. Getty Images Tottenham vs Arsenal player ratings Kieran Gibbs - 4 Made little impact on the game. Another player who looked out of their depth. Getty Images Tottenham vs Arsenal player ratings Mesut Özil - 4 Another game in which he went missing. Dreadful display. Getty Images Tottenham vs Arsenal player ratings Alexis Sánchez - 6 Like Ramsey, the Chilean took a while to get going but by the end of the first half he was starting to have an influence on the run of play. Went off the boil in the second half though. Getty Images Tottenham vs Arsenal player ratings Olivier Giroud - 6 Willing to get back and help out his team mates defensively but failed to provide any real danger and creativity up front. Getty Images

“I didn’t speak to him about it because I only heard about it today,” he added. "I will speak to him about it a little bit because I don't know what happened and it is always good to get the players side of it."

The reaction from Özil once again casts doubt on Arsenal’s ability to cope mentally with pressure in big matches, with the Gunners taking the fewest points from games between the top six in the Premier League this season.

With the news of Aaron Lennon’s stress-related illness emerging this week, extra attention is being put on the mental state of footballers and the help that is available to them in a sport where there has not always been the availability to treat mental health issues, and Wenger was asked both about his own team and the wider impact that the game can have on individuals.

“I felt away from home we failed in big games yes and didn’t take enough points,” Wenger said of their games against Chelsea, Spurs, Liverpool, United and Manchester City. “[It’s] Difficult to explain because last season it was the reverse.

Wenger could not explain why Arsenal have lost big games this season (Getty)

“There was a turning point at Everton and Man City where we lost two games on the trot. It took our confidence away from us. It is always difficult to isolate one factor. Defensively away from home we have conceded too many goals.”

The pressure is very big and it is not easy to deal with that at a very young age <p>Arsene Wenger</p>

He added on questions about mental health in football: “We help on the mental front players who want help of course. It is different for the players when they do not meet their needs, like all of us they are frustrated and they suffer with self-esteem in certain situations because the expectation on them is high.

“The pressure is very big and it is not easy to deal with that at a very young age. We try to help them yes. Clubs have that network of help available but not all players even if they feel the need they want to be helped by people at the club.