Johnson, 45, was replying to his fans on Twitter who were praising him for his performance in his recently-released movie "Baywatch", when one of the actor's Argentinian admirers complimented him for having "beautiful feet".
The actor replied, saying even Hart "calls my feet beautiful too".
To this the "Central Intelligence" actor wrote back to Johnson and joked, "Your a damn lie(r)... Your feet look like @MichaelPhelps hands... They're disgusting... Sorry Mike LMAO."
The former wrestler replied with another funny comeback, playfully chiding Hart for dragging the most decorated Olympian of all time in their conversation and said his hands appeared like "burnt cabbage".