Arsenal chief Ivan Gazidis rates manager Arsene Wenger as irreplaceable.
Wenger signed new terms with the Gunners last month.
Gazidis said: "We are all really pleased with securing Champions League qualification again. Last season was a great experience for players to win the FA Cup and now we want more.
"Arsene is impossible to replace. He has given us the footballing philosophy we have now.
"Arsene's legacy is based on him wanting to take Arsenal to the next level, and everything he did and still does is for the future of the club."
