Chelsea have sacked manager Thomas Tuchel on the new owners' 100th day in charge after their third defeat of the season.
Owner Todd Boehly has placed Tuchel's coaching staff in temporary charge until a replacement is found.
A club statement said the owners believed it was "the right time" to bring in a new head coach.
BBC Sport understands the decision would have been taken regardless of the 1-0 defeat in Chelsea's Champions League opener at Dinamo Zagreb on Tuesday night.
It is also understood that Chelsea will make a swift appointment and among the bookmakers' favourites to take over are Brighton manager Graham Potter, former Spurs and PSG boss Mauricio Pochettino, former Real Madrid manager Zinedine Zidane and current Leicester boss Brendan Rodgers.