Arsene Wenger did not inform anyone of his decision to leave Arsenal until just minutes before an announcement was made, according to a report.
The 68-year-old, who signed a two-year contract extension at the Emirates Stadium last summer, was due to have his position reviewed at the end of the season.
Rather than wait until then, though, the Frenchman made the decision to step aside of his own accord, with a statement being released on Arsenal's official website shortly before 10am on Friday morning.
Wenger did not tell his players or coaches about the imminent revelation until the last moment, it is claimed by The Sun, and they were all taken by surprise when hearing the news.
Arsenal have now started their search for a replacement, with chief executive Ivan Gazidis hinting that the Gunners will pick an outside choice.