Mauricio Pochettino has left Chelsea after just one season in charge by mutual consent, the English club announced on Tuesday.
The Blues finished sixth in the Premier League thanks to a fine run towards the end of the season but missed out on Champions League qualification and a trophy.
"Chelsea FC can confirm that the club and Mauricio Pochettino have mutually agreed to part ways," Chelsea said in a statement.
In just two years under the ownership of an American consortium fronted by LA Dodgers co-owner Todd Boehly and private equity group Clearlake Capital, Chelsea have spent over £1 billion ($1.3 billion) on new players.
The vast majority of that outplay was spent on rising stars and Pochettino pointed to a lack of experience and a lengthy injury list for failing to achieve consistent results.
Chelsea lost the League Cup final 1-0 to Liverpool after extra-time and pushed Manchester City all the way before losing in the FA Cup semi-finals by the same score.
But there had been signs that Pochettino's project was coming together in a run of five consecutive wins to end the season that ensured Chelsea will be in Europe next season.
They will qualify for the Europa League if Manchester United lose to City in the FA Cup final and the Conference League if the Red Devils shock the English champions.
"Thank you to the Chelsea ownership group and sporting directors for the opportunity to be part of this football club's history," said Pochettino.
"The club is now well positioned to keep moving forward in the Premier League and Europe in the years to come."
Chelsea sporting directors Laurence Stewart and Paul Winstanley said: "On behalf of everyone at Chelsea, we would like to express our gratitude to Mauricio for his service this season.
"He will be welcome back to Stamford Bridge any time and we wish him all the very best in his future coaching career."