Arsenal assistant manager Steve Bould admitted the Gunners are short of confidence and energy after Schalke inflicted their first home defeat in the Champions League group stages for nine years.
Arsene Wenger's side were out-fought and out-thought by Schalke as late goals from Klaas-Jan Huntelaar and Ibrahim Afellay secured a shock 2-0 victory on Wednesday that took the Germans top of Group B.
It was Arsenal's first home loss at this stage of Europe's elite club competition since Inter Milan won at the Gunners' old Highbury stadium in 2003.
The Emirates faithful responded by booing their team off the pitch at full-time. With frustration growing among the Arsenal fanbase after seven trophy-less years, there are certain to be some difficult questions for Wenger at the club's annual general meeting on Thursday.
Coming just five days after Arsenal produced an equally tame display in a 1-0 loss at struggling Norwich in the Premier League, this lacklustre effort prompted Bould to concede his team was stuck in a rut.
"We haven't played anything like we can, that's the big disappointment," Bould said.
"We looked jaded. I don't know why that is. We don't look confident on the ball at the moment.
"It's not what we are accustomed to. We normally create chances and we need to correct that.
"We lack a bit of confidence for whatever reason, but it's a tough competition. They are a good side."
Bould believes Arsenal's already fragile confidence is taking a major dent whenever they concede the first goal at present and he hinted changes could be made for Saturday's clash against QPR.
That would likely mean a first appearance for 18 months for England midfielder Jack Wilshere, who is returning from a series of injuries. Alex Oxlade-Chamberlain could also feature after a hip injury.
"In the West Ham game we looked really sharp but since returning from the internationals we've looked jaded. We need to pick it up again," Bould said.
"Scoring first will be a major plus for us at the minute. We've gone behind in the last five games or so and coming back can be hard at times.
"One or two might need freshening up on Saturday. Jack and Alex could be available."
Coming up in the group stages is a tricky trip to Schalke up next and an away game at Olympiakos, where Arsenal have lost in the past. Bould acknowledged the Gunners will have to improve to qualify.
"Of course they are frustrated. We are as well. We don't like losing games," he added.
"We have got nine points to play for and wherever we get the points from doesn't matter. We will perform a damn sight better than this in the next match."
Meanwhile, Schalke coach Huub Stevens claimed his side's impressive display didn't mean they were favourites to maintain their one-point lead over Arsenal at the top of the group.
"Arsenal is the favourite in this group. When they have all the players fit they are the favourites," he said.
"We have won two games on the road and we have seven points. I have to be happy but there is still a long way to go.
"We will have a chance when Arsenal come to Schalke but we must play better than in the first half here."
Although Stevens insisted Schalke's victory was well deserved, he conceded they should have made their dominance pay much earlier than the final 14 minutes.
"At the start we were a bit cagey and had too much respect for Arsenal. We didn't show enough courage. They were the better team in the first half," he added.
"But we didn't allow any chances and in the second half we gave the right answer. We can say 2-0 was a deserved win for us."