Arsene Wenger is to leave Arsenal at the end of the season, ending a near 22-year reign as manager.
The Frenchman departs a year before his latest contract was due to expire.
The Gunners are sixth in the league and set to miss out on a top-four spot for the second straight season, with their hopes of reaching the Champions League resting on winning the Europa League.
Wenger, 68, won three Premier League titles and seven FA Cups, including the Double in 1998 and 2002.
“I am grateful for having had the privilege to serve the club for so many memorable years,” said Wenger. “I managed the club with full commitment and integrity.
“To all the Arsenal lovers, take care of the values of the club.”
Arsenal say a successor will be appointed “as soon as possible”.
Arsenal tweet announcing Arsene Wenger’s departure at the end of the season
Arsenal majority shareholder Stan Kroenke described Friday’s announcement as “one of the most difficult days we have ever had in all our years in sport”.
He added: “One of the main reasons we got involved with Arsenal was because of what Arsene has brought to the club on and off the pitch.
“His longevity and consistency over such a sustained period at the highest level of the game will never be matched.”
Arsene Wenger Premier League stats: Games 823, wins 473, losses 151, goals scored 1,549, league titles
The American praised Wenger’s “exceptional record”, adding that he “transformed the identity of our club and of English football with his vision for how the game can be played”.
Appointed on 1 October 1996, he is the Premier League’s current longest-serving manager and has taken charge of a record 823 games.