Cesc Fabregas has warned his Arsenal team-mates they must learn to close out games if they are to be successful in this year's Champions League.
The Gunners host Dutch champions AZ Alkmaar at Emirates Stadium on Wednesday just two weeks after they conceded an injury-time equaliser in the reverse fixture in Holland.
Arsenal dominated most of the game and had several chances to seal the victory after captain Fabregas had given them an early lead.
The draw resulted in Arsenal losing their 100% Champions League record before they then went on to surrender a two-goal advantage at Barclays Premier League strugglers West Ham the following weekend.
The Gunners captain hopes his side will have learned to be more ruthless by the time they play the Dutch side again on Wednesday.
"We must learn from these games. We have to do better," the Spain midfielder said.
"Of course we wish we could score four or five goals in every single game, but we must realise that sometimes that is not the way football is and sometimes to win the games, you just have to not make mistakes and work hard to keep the ball better.
"But it is always hard to go away in the Champions League and get a result, so we cannot be too disappointed with the draw against AZ.
"Another positive is that we are scoring goals, and that is the hardest thing to do in football, which says a lot about us.
"But on the days when we can't score more, we need to kill the game off in other ways, by passing the ball more and keeping possession."
Wenger knows a win against Ronald Koeman's team will put his side on the brink of qualification for the second stage of Europe's elite competition for the 10th consecutive season.
The Arsenal boss ordered his side to play the ball into the corners in the dying minutes of the midweek Carling Cup win over Liverpool.
He rejects the accusation his side lack the concentration and determination to shut out games, however.
"I don't believe at West Ham we switched off at all and I don't believe at Alkmaar we switched off," the 60-year-old said.
"In the Champions League you look at the results, 50% of the goals are conceded basically in the last five minutes and at West Ham I believe we were really unlucky. "We were focused and we were unlucky with the free-kick, we were unlucky with the penalty. I don't believe either of those was the right decision."
Samir Nasri could be in line for only his second start of the season after he played all 90 minutes of the Liverpool win.
Another player who is likely to make a return to the side is Tomas Rosicky, who has been plagued by knee and hamstring injuries for the majority of his time at the club since signing in 2006 from Borussia Dortmund.
The Czech Republic midfielder, who is out of contract at the end of the season, returned to first-team action in September after 18 months out.
He then played seven games before suffering a setback in his recovery but should be back for Wednesday's game.
"Tomas Rosicky is like many players who we have had out," Wenger said.
"He has been given the all clear from a scan but still has pain. It should be a question of days rather than weeks. We hope he will be fit for Wednesday or next Saturday."