Wenger has warned that he will not make a decision on his long-term future until later in the season to leave Arsenal fans wondering whether he will sign the deal which is on the table.
Petit said: "I'm sure Wenger will stay with Arsenal, it's impossible to imagine the club without him. If the club does not win a trophy then it will be hard for him, but I think they will.
"But the fans must understand that he has been the best thing to ever happen to Arsenal and he is responsible for all the success in the past 17 years."
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