Shkodran Mustafi insists Arsenal players can only blame themselves for their midweek defeat to Watford, and must be better prepared mentally to face Chelsea.
Arsene Wenger said the Gunners "missed the first half" against the Hornets and were not "ready for the challenges" as they were beaten 2-1 at the Emirates.
The defeat was Mustafi's first since joining in the summer, and leaves the Gunners nine points behind Premier League leaders Chelsea ahead of their meeting on Sky Sports on Saturday.
Asked whether the players or manager should take responsibility for the result, and the slow start, Mustafi told Sky Sports: "Personally I think the first thing you do is blame yourself first. The most important thing is to look what you have done wrong in the game. Then blame others.
"The players are on the pitch, we blame ourselves before we blame the manager. We have to take that responsibility and then answer."
Former Liverpool striker Dean Saunders told Premier League Daily that Arsenal need a "change of mentality" after their defeat to Watford.
And Mustafi acknowledged: "It can only be mental. We know we can play better and we were sloppy at the start.
"It's all about mentality, being there from the first minute and knowing the Premier League is a difficult competition and teams are going to go for the opportunity they have, which Watford did. They ran at us and defended well. We were not clever or concentrated enough to stop them.
"We were not there, they ran all over us, and we cannot be happy with that at home. We have to bounce back, it's a big game against Chelsea, we will try to be there from the first minute to the last second."
Reflecting on his first defeat as a Gunner, Mustafi added: "It's not the first game I have lost in my career, so I know how to handle it. Obviously I am disappointed, we are all, because we could have done better.
"But in the end, as I said, we have to move on. We have an opportunity to go out and make things right. All of my team-mates think the same."
Arsenal beat Chelsea when they met at the Emirates earlier in the season, scoring three times in the first half to secure a comfortable 3-0 victory.
But Antonio Conte's side have lost just once in the league since then as they have soared to the top of the table.
"It's a completely different situation; it's going to be a completely different game," says Mustafi. "We have to be really focused from start to finish because they have a good side, they have been playing well and they have a plan and identity of how they want to play.
"It's going to be difficult but it's an opportunity to make things right."