Arsène Wenger has admitted there is a danger that Arsenal could establish a habit of throwing away victory in games after Tottenham Hotspur beat them 3-2 at the Emirates on Saturday.

Goals from Samir Nasri and Marouane Chamakh gave Arsenal control of the north London derby before Wenger saw his team crumble after the break, with a Spurs fightback culminating in Younes Kaboul's winner in the 85th minute.

Arsenal play Braga tomorrow at the Estádio Axa in their penultimate Champions League group game knowing a point will secure them qualification to the knockout stages. Yet they lost their previous game against Shakhtar Donesk 2-1 having taken the lead, and in the league earlier in the season also allowed Sunderland a 90th-minute equaliser.

Asked if this inability to close out matches could develop into a mental problem Wenger said: "That is the danger. Mentality can become an issue. I don't think it will be but that's the fear. If it's repeated then it can become something that can block the team.

"It is down certainly to sometimes easing up in games because maybe subconsciously we feel the need to go through the motions. And sometimes a more subtle subconscious feeling that we have not won yet and get a bit nervous when we have to become really concrete."

But Wenger stated that he would not yet employ a specialist to help his players. "No. Unless you have one specific problem which [a] psychologist can help to sort out then [I do not believe in this]. We are not at that point at the moment," he said.

Instead the Frenchman believes concentration on performance is the best way of overcoming the problem. "You focus on the technical side of your play and not on the expected result," he said. "I want this team to win so much, that I am giving every drop of my blood to make sure this team wins."

Wenger will be without Gaël Clichy due to a back problem and, despite the importance of the game, he has decided to rest Andrey Arshavin and leave Robin van Persie behind to work on fitness. While Wenger would only confirm that Kieran Gibbs definitely starts at left-back in place of Clichy, the manager said there was no issue with Nicklas Bendtner following his recent comments that he needed to start regularly. He also hinted that the Dane may play ahead of Chamakh as the striker "has played a lot of games" recently.

Cesc Fábregas, the Arsenal captain, has travelled despite Wenger admitting he is still carrying a hamstring injury. "Sometimes after the game he has a little recurrence, but at the moment I do not want to take a massive gamble. We cannot afford to lose him, so I check every morning of the game how he is and we monitor him quite well, but it is on the way up," he said.

Wenger added that the problem may be mental. "He was out for a while and had a reoccurrence of his problem. Then it gets in your head. When it gets in your head, it is difficult to play free of your mind," he said.

Arsenal routed Braga 6-0 in the reverse fixture in September but Wenger believes the manner of Spurs' first league victory at their home since 1993 will sharpen focus.

"With what happened to us against Spurs everyone will be focused and want to perform at our best," he said.

"It was difficult yesterday more than today because now we are in front of [another] game. We have a healthy spirit and a very ambitious spirit. The players were very, very down. They know that they basically threw the game away that was in our hands."

Despite the defeat to Spurs Arsenal are still only two points from the top of the league due to Chelsea's faltering form. Wenger stated this is the most open title race since he can recall. "At this stage of the season, I have never seen a league as compact as it is at the moment," he said. "You cannot deny that mathematically it is [also] possible for Spurs and Manchester City to become champions."