Arsenal, after two disappointing defeats to Manchester City and Chelsea, need to pull up their socks and show what they are truly made of when they take on West Ham in their English Premier League game.
The Gunners are in serious danger of drifting too far away from a Champions League place, and currently lie seven points behind fourth-placed Tottenham. This game in hand against West Ham at the Emirates - the postponed Boxing Day match - will pull them to within four points, a much more manageable deficit; but only a win will do.
Losses against City and Chelsea showed Arsenal one thing - getting quickly out of the blocks is extremely important in a Premier League game, especially a big one. Those results have made the West Ham match as vital as any, with only three points acceptable.
"I don't question the players' character but then you look at the consistency of the results in the big games," the manager said.
"The attitude of the players is fantastic. They want to do well and are focused, but are maybe a bit too respectful in the big games. Every time we start to show what we can do, the game is already lost. That is what we have to change.
"The players come out and think 'we could have done better.' But when you look at the first half we lost goals that we shouldn't lose and 50-50s you cannot lose in big games.
"You have to go with a mentality in big games based on belief and total commitment."
Arsenal clearly lack that confidence that separates the big teams from the rest. Having not won a single trophy for over seven years, for a club with Arsenal's magnitude, is not something you get over too easily. That pressure can either make or break you, and right now it is doing the latter.
"We don't want to be in this position," Wenger added. "We want to challenge for the championship and therefore now until the end of the season we really have to stand up and show our strength and character.
"Last season we came from further behind and finished third but Chelsea are a bit away from us now. The game that we lost at Chelsea on Sunday had difficult mathematical consequences."
Arsenal will be without Mikel Arteta, Tomas Rosicky and Francis Coquelin, who picked up a hamstring problem in the Chelsea game. Lukas Podolski and Alex Oxlade-Chamberlain, who missed the last match due to illness, are expected return.
West Ham have no new injury worries, with Andy Carroll, George McCartney and James Collins ruled out, while on-loan forward Marouane Chamakh is ineligible to play against his parent club. Modibo Maiga also misses as he is on Africa Cup of Nations duty with Mali.
The Gunners' title hopes might have vanished without a trace, but there is still the F.A. Cup and the Champions League, with a daunting tie against Bayern lying in wait.
Confidence breeds good results, and if Arsenal go on a run of wins, anything is possible.
West Ham is as good a starting point as any.
Expected lineups: Arsenal: Szczesny; Jenkinson, Mertesacker, Vermaelen, Gibbs; Diaby, Ramsey; Oxlade-Chamberlain, Wilshere, Cazorla; Walcott.
West Ham: Jaaskelainen; Demel, Tomkins, Reid, O'Brien; Noble, Diame; Cole; Nolan, Jarvis; Chamakh.
Prediction: 3-0 to Arsenal
