Di Matteo became the sixth Chelsea manager to lose his job since Mourinho's exit in 2007, paying the price for a bad recent run of results that has left the Blues' Champions League hopes hanging by a thread.
But Mourinho takes no pleasure from Di Matteo's misfortune.
"I am never happy when a manager is sacked," he said.
"It can happen to me so I never enjoy it. I always feel sorry for him and his family.
"Our lives are very similar. I am not happy with any situation."