Arsene Wenger announced on Friday that he is stepping down as Arsenal manager at the end of the season, bringing an end to a 21-and-a-half-year reign that brought unprecedented early success but has seen a late decline that made his position increasingly untenable.
Wenger issued a statement that caught everyone by surprise, announcing his departure and thanking the club for letting him serve for "so many memorable years."
"After careful consideration and following discussions with the club, I feel it is the right time for me to step down at the end of the season," he wrote. "I am grateful for having had the privilege to serve the club for so many memorable years.
"I managed the club with full commitment and integrity. I want to thank the staff, the players, the Directors and the fans who make this club so special. I urge our fans to stand behind the team to finish on a high.
"To all the Arsenal lovers take care of the values of the club. My love and support for ever."
Arsenal said a new manager will be appointed "as soon as possible," and speaking at a news conference later on Friday, club CEO Ivan Gazidis said the hiring process would "start today."
Speaking to reporters a day before his announcement, Wenger said New York City FC coach Patrick Vieira "has the potential" to succeed him as manager one day, when asked about reports linking the former Arsenal captain with the job.
According to reports, Wenger asked Arsenal to hold off announcing his decision to leave the club so he could inform his players first, which he did ahead of training at their London Colney base, minutes before the news was made public by the club.
"We didn't see it coming," midfielder Jack Wilshere said. "He had another year left on his contract. Ever since I've known about Arsenal, Arsene has been there. I'm sad."
His coaching staff were also reportedly informed of the decision in advance, although club staff working at the Emirates Stadium rather than the training ground discovered the news at the same time as everyone else.
Speculation surrounding the Frenchman's future has been rampant in recent months, with Arsenal set to miss out on a top-four finish in the Premier League for the second year running. Still, there was a general feeling that he could still save his job and see out the remaining year of his contract if Arsenal won the Europa League, thus qualifying for next season's Champions League.
But Friday's unexpected announcement ensures that Wenger will be given a send-off fitting for a man who many consider the greatest manager in the club's history.
The Frenchman was largely unknown in England when he was appointed in 1996 but led the team to a domestic double in 1998, the first of three league titles and seven FA Cups he has delivered.
But the last of those league titles came in the unbeaten "Invincibles" season of 2003-04, and fans have grown increasingly restless with the failure to challenge for the Premier League crown in recent years. Despite three FA Cups in the past four seasons, calls for his resignation have steadily grown, and reached a peak this season as the Gunners limp toward their worst league finish of Wenger's reign.
Wenger himself gave no hint whatsoever during Thursday's news conference that he was about to step down and has previously said he would respect his contract.
Majority owner Stan Kroenke said in the statement that parting ways with Wenger was "one of the most difficult days we have ever had in all our years in sport."
"We have high ambitions to build on Arsene's remarkable tenure and to honour his vision by ensuring that Arsenal competes for and wins the biggest and most important prizes in the game," the American added.
"We must now focus on making a strong finish to the season and ask our millions of fans around the world to join us in paying appropriate tribute to one of the greats of Arsenal's history and one of the greats of the game."