Leicester City manager Claude Puel has warned Arsenal that it may take "a few years" before they fully adapt to life without Arsene Wenger.
The long-serving Gunners boss, who spent time in the same side as Puel during their playing days at Monaco, is to stand down this week after 22 years in North London.
Wenger's penultimate game in charge comes against Leicester on Wednesday evening, before bringing down the curtain with a trip to Huddersfield Town on Sunday.
A number of high-profile names have been linked with the soon-to-be-vacant position, including Massimiliano Allegri and Luis Enrique, but Puel believes that it will be nearly impossible to truly replace Wenger.
"Wenger is a great loss for Arsenal," he said at his pre-match press conference. "After a few years they can come back at a good level. But it is difficult when a club have had success like this and must replace the manager and sometimes replace valuable or great players.
"It will be difficult for the new manager. Perhaps the new manager or great managers will like different options or possibilities. I hope the fans and club do not regret their choice, because he has had a massive impact as manager of Arsenal for 22 years.
"How can you replace him? It is always tough - like after Sir Alex Ferguson at Manchester United. [Wenger] has had a lot of possibility to manage different clubs and great clubs in Europe and he stayed always, to give his best and continue to build. If he goes to other clubs, he can have a fantastic team and can perhaps win the Champions League."
Leicester have not managed a single win against Arsenal in 22 games, drawing seven and losing 15 of those.
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