Arsenal majority owner Stan Kroenke has said that the "longevity and consistency" of Arsene Wenger during his time at the Gunners will never be matched.
On Friday, Wenger announced that he will step down from his role as manager at the end of the season with Arsenal facing the prospect of a second year without Champions League football.
Wenger has received strong support from Kroenke throughout his reign at the North London outfit and the American - who owns a number of teams in the United States - has acknowledged that news of Wenger's departure is one of his "most difficult days" in sport.
Kroenke told the club's official website: "This is one of the most difficult days we have ever had in all our years in sport. One of the main reasons we got involved with Arsenal was because of what Arsène 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 has unparalleled class and we will always be grateful to him. Everyone who loves Arsenal and everyone who loves football owes him a debt of gratitude. Three Premier League titles, including an entire season unbeaten, seven FA Cup triumphs and 20 successive years in the Champions League is an exceptional record. He has also transformed the identity of our club and of English football with his vision for how the game can be played.
"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."
Arsenal and Wenger are still attempting to win the Europa League, which would secure a spot in next season's Champions League.