The Marseille boss, who spent a season at Chelsea before the Abramovich takeover, believes the sacking of Ray Wilkins and disruption behind the scenes has reverberated through the club and impacted on manager Carlo Ancelotti.
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'I know Carlo and Ray very well,' said Deschamps. 'There was a lot of respect and confidence and sincerity between the two of them and I don't think it's a good thing for Carlo to have lost Ray Wilkins. I think it could possibly have unsettled the players.
'Ancelotti has a certain power but he has people above him, a president, who decides. He has to accept it and adapt to it.
'It's crucial for a manager to be able to depend upon the ability of his staff and have complete confidence in them.'
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Wilkins was sacked last month, with Abramovich appointing his friend Michael Emenalo as the new assistant manager.
Ancelotti will pick his strongest side for tonight's Champions League tie in Marseille and demand a win from his misfiring Chelsea stars, despite their already being assured of top spot in Group F.
Ancelotti had planned to rest several senior players to keep them fresh for games against title rivals Tottenham, Manchester United and Arsenal. But, after a loss of form, he will risk fatigue and injuries in the hope his side can recapture the winning habit.
Ashley Cole is out with a troublesome ankle while a swollen knee sidelines Nicolas Anelka. Frank Lampard, Alex, Yuri Zhirkov and Yossi Benayoun are also injured but nobody will be given a breather, although Josh McEachran may get another start in midfield.
'It is important to have a good performance,' said Ancelotti. 'This could be an opportunity to improve confidence. For this reason, we need to put the best line-up possible on the pitch.
'This is an important game, maybe even a key game, although I would say the real key games are the ones we have to come now against Tottenham, United and Arsenal.'
Chelsea have taken only five points from their last six Premier League games. Ancelotti wants John Terry, Michael Essien and Didier Drogba to play their way back into top form after various fitness problems.
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