Antonio Conte admitted that Chelsea "are a great team only on paper" after watching Arsenal demolish his team 3-0 at the Emirates Stadium on Saturday.
First-half goals from Alexis Sanchez, Theo Walcott and Mesut Ozil secured the Gunners' first Premier League victory over their London rivals since October 2011, with a lacklustre Chelsea failing to register a single shot on target until the 82nd minute.
The Blues lie eighth in the Premier League table after comprehensive defeats against Liverpool and Arsenal. And after the match, Conte conceded that his players are falling short of their illustrious reputations on the pitch.
"What happened? I think from the first minute we didn't have the right attitude," Conte told BT Sport. "I think we played a bad game against a tough team, very organised, very prepared in the tactical physical aspect.
"I think that after today we are thinking that we must work a lot, because now we are a great team only on paper."
Arsenal were gifted their opening goal after just 11 minutes when Sanchez dispossessed Gary Cahill before running through on the Chelsea goal and dinking the ball over Thibaut Courtois. But Conte reserved his postmatch criticism of the Blues' performance for the entire team.
"I don't want to talk about the mistakes because it's not right for the player," Conte said. "We win as a team, we lose as a team. We know we must work a lot and if someone thinks this team now is ready to fight, I think we must wait and work to improve a lot and to come back a great team not only on paper, but on the pitch."
Asked about the failure of Eden Hazard and Diego Costa to impact the match, Conte added: "I think it's always a team problem, not an individual player.
"If the team works, the individual players play a good game. When nothing works, it's very difficult for individual players to play a good game."
Defeat to Arsenal sees Chelsea fall eight points behind Premier League leaders Manchester City after just six matches. However, Conte insists he is more focused on the problems at Stamford Bridge than the achievements of rivals.
"Manchester City started the season very well," the Italian said. "They play well but also everyone must look in our house for the problem. Now it's important to look in our house and not in other houses."