Chelsea chief Avram Grant claimed he laid into his stars to spark their 2-1 comeback win on New Year's Day.
But it was actually Clarke who read the half-time riot act.
A Blues insider revealed to The Sun: "Grant said his piece but didn't raise his voice.
"Then Steve tore into the players and told them they were not performing like internationals.
"He questioned their desire and asked if they could honestly say they were doing their best."