In their next 12 league games, the Blues have only won six times and have tasted defeat on five occasions.
Le Saux played more than 200 league games for Chelsea in two spells, winning the European Cup Winners Cup, the League Cup and Uefa Super Cup.
"In that moment I wanted to talk with them alone, without anybody else", he said.
Several aspects of that plan were in need of improvement, he said.
He explained his decision by saying he "needed to understand" the performance and why the first and second halves were "so different". But I have not seen Sarri do it. "We can lose, of course, in every match, but not in this way". Suddenly after the first goal we were not able to play. Captain Cesar Azpilicueta said: "Afterwards we spoke as men between the manager and the players".
Wales winger David Brooks created King's 47th-minute opener before coolly doubling Bournemouth's advantage, although he pulled up on a subsequent attack to cut a wonderful display short. But not with that kind of reaction.
"So I love my job for everything, but I know very well the rules".
Sarri says his side did not play as a team after the break and they "found it hard to accept" going behind.
Chelsea's fans looked on in shock as their team crumbled, and when loanee Higuain was hauled off, some of them sang: "You don't know what you're doing" to Sarri.
The Welshman was the star of the show in the 4-0 demolition of Chelsea in midweek but the 21-year-old picked up an issue and Eddie Howe will have to make do without him for the next month.
Other than that, loan deals bringing Gonzalo Higuain to Chelsea and Denis Suarez to Arsenal were the only moves that caught the eye for the top teams.
Speaking at a media conference on Friday afternoon, Sarri was asked about his apparent reliance on Jorginho, who played under him at Napoli and was his flagship summer signing following his appointment as Chelsea head coach.
So it was telling that in a recent interview with France Football magazine, Hazard was quoted as saying: "In my career I have frustrated all of my trainers". I didn't see the signal of my work. It's clearly not working for Sarri at Chelsea - with the manager publicly stating that he can't motivate his players.