Arsene Wenger has called on Arsenal to provide the "perfect" response and show their true quality by beating Standard Liege to qualify for the knockout stages of the Champions League.
The Gunners had looked sublime before the international break, moving above Manchester United and closing in on Barclays Premier League leaders Chelsea following a 13-match unbeaten run across all competitions.
Yet the 1-0 defeat at Sunderland - where Arsenal were without injured Holland forward Robin van Persie and well-short of their usual free-flowing selves - has once again been highlighted as just why Wenger's squad are not quite yet the finished article.
A draw tonight would be enough to see Arsenal safely through with a match to spare, while victory will win them Group H and provide the ideal preparation for Sunday's visit of Chelsea.
Wenger declared: "We have a good opportunity to finish first in the group and qualify, then after we can think about Chelsea.
"The perfect way is to respond after a disappointing result, that is where you judge a big team and that is what we want to do."
Wenger, though, remains less than impressed by the lacklustre performance at the Stadium of Light.
He said: "We had some deficiencies which we paid for and we have to make sure that is not repeated.
"We did not produce enough in the final third, which had been our strength until now.
"We did not have the right fluency in our game, nor enough penetrative runs to force the issue in the final part of the pitch.
"That is why we were not dangerous, rather than down to any individual.
"I do not deny at all the super-class of Van Persie, I just feel we still have enough in the locker to score goals even when Robin is not there."
Arsenal will have England Under-21 defender Kieran Gibbs available again after a foot injury, and Theo Walcott is expected to get some more much-needed game time after what has been an injury-hit start to the campaign.
Both men are among several Arsenal players hoping to be involved at the World Cup next summer.
Wenger, though, wants all of his team focused on the here and now.
"For me, the big season is with Arsenal, not at the World Cup," Wenger insisted.
"We do not pay players to go to the World Cup - we pay the players to do well for Arsenal.
"The first pride of a man is to do well for the guy who pays you in life, not to go to the World Cup."