The Italian coach has been widely praised for revolutionising Chelsea’s style of football and having an impact on the Premier League following his switch to a 3-4-3 formation.
Chelsea won the Premier League title with seven points to spare last season after a run of 13 successive top-flight victories between October and January.
However, the Blues have already lost to Burnley and Crystal Palace in the Premier League this season to raise concerns about their title credentials.
The title holders were thoroughly outplayed as Manchester City were 1-0 winners against Chelsea thanks to Kevin De Bruyne’s winner at Stamford Bridge.
The west London side lost 3-0 to AS Roma in the Champions League on Wednesday night to concede 13 goals in their last six games.
Former Arsenal defender Keown admitted Chelsea are in crisis ahead of the visit of Manchester United at Stamford Bridge in the Premier League this weekend.
“Chelsea are struggling,” Keown told the Daily Mail.
“Teams are now looking at their system and finding ways to punish them.
“The game was up when they were beaten by Manchester City. Chelsea knew they were second best that evening.
“For the City players, their toughest test of the season came against Napoli, not the English champions.
“Chelsea have looked like conceding in almost every match this season. They may have showed fight to come back from 2-1 down to beat Watford but they could easily have lost that game.
“Antonio Conte has talked about hunger and hard work but really it is about belief. It looks like these Chelsea players no longer have belief.”
Chelsea have won the Premier League title in two of the past three seasons under Jose Mourinho and then Conte.
The Blues signed six players in the summer transfer window.
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