Conte took training when some of the Chelsea squad returned for pre-season this week but has always been expected to be replaced this summer.
The sacking brings to an end a fractious two-year relationship between Chelsea and Conte.
Sarri is central to Chelsea's 14th change of coach since Roman Abramovich arrived in 2003, although yet again there will be a costly severance payment to the outgoing coach.
Chelsea seeks a 13th permanent manager under Abramovich's ownership, and at possibly the most turbulent period of the Russian billionaire's trophy-filled reign. "Good luck for the future".
However, while present players may have had issues with Conte, former Chelsea legend John Terry, who left after the league title winning campaign had nothing but praise for him.
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He was removed from the Russian Federation investigation previous year after the texts were discovered. Strzok, you are under subpoena and required to answer the question", Goodlatte added.
Conte leaves with the best win percentage 65.1 per cent of any of Chelsea's managers in the Premier League era.
Chelsea have until August 9 to complete all their summer purchases.
Jose Mourinho: Premier League 04-05, 05-06, FA Cup 06-07, League Cup 04-05, 06-07. Only the pay was improved, though, with Conte's contract still running for just another two seasons - hardly a show of commitment by either the club or its manager.
Antonio Conte: Premier League 16-17, FA Cup 2017-18.
Incredibly the club have released a statement thanking Conte for his services to the club, but the message only consisted of 52 words.
Chelsea have endured a turbulent summer so far with managerial uncertainty meaning they've yet to make a major signing so Jorginho is expected to become the first new arrival at Stamford Bridge.