Rome: Antonio Conte's return to Italian football on Tuesday proved such a chastening experience as he watched his Chelsea side dismantled by AS Roma in the Champions League that he worries they could be set for a "very difficult" season.
A downbeat Conte said he and his players all had to take responsibility for the 3-0 capitulation in Group C, which equaled the biggest he has suffered in his Chelsea reign, and needed to rediscover their hunger for battle quickly.
Chelsea's Thibaut Courtois, whose second-half saves kept the score down, was also baffled by how the Premier League champions lost their "fighting spirit" after half-time as they became the first English side to lose in the Champions League this season.
Two first-half goals from Stephan El Shaarawy seemed to break Chelsea's spirit to such an extent that after the break they were both so disorganized at the back and careless with their distribution that they bore no resemblance to the efficient outfit who were so hard to breach last season.
After Diego Perotti made it 3-0, Conte told BT Sport: "Roma showed more will to fight and more desire to win the game. For this performance, we all have to take responsibility.
"When you concede three goals, you must be worried. It means something doesn't work."
Talking to Sky Sports, he added: "This season will be very difficult if we don't understand quickly the right way that we have to go.
"Last season we showed great hunger, great will to do something of importance. If we think that only because our name is Chelsea and the opponent has fear (of) the name Chelsea, I think this is not the right way.
"We must find the hunger that we showed in all last season and in this season sometimes. We have to try to find the strength to understand and to use this loss in the right way."
Conte has cut a restless figure all season with Chelsea's Premier League title defense having been so underwhelming as they lie nine points off the leaders Manchester City.
Increasing media speculation about Conte being replaced at Stamford Bridge by compatriot Carlo Ancelotti also left him uncharacteristically irritable at a news conference last week.
Yet he seems even more exasperated with what he is seeing on the field, Chelsea's woeful defending in the Stadio Olimpico on Tuesday making him wish aloud that such a performance was for "one night only".
The evidence, though, is that a lack of confidence is infecting his previously mean rearguard, as shown in particular by the lack of communication between Antonio Rudiger and his fellow defenders which led to El Shaarawy's second goal.
"I don't know why in the second half we dropped our fighting spirit and our mentality," Courtois told BT Sport. "We have to fight back on Sunday (in the Premier League clash with Manchester United) and show the fans this was an off-day."
The only good news for Chelsea was that Atletico Madrid's shock home draw against Qarabag in the other Group C fixture meant the London side only needs one win from its final two games to ensure qualification for the knockout stages.