The 68-year-old Frenchman announced that he would be stepping down at the end of the season after 22 years in charge last month.
"We are trying to think about our team, little touches, little replacements - a Michael Carrick replacement, this kind of situation - but until now I didn't lose one second thinking about a Marouane replacement".
Wenger accepted his unusually cordial welcome from United in the manner it was intended, but could not shrug off the frustration of losing.
Wenger was applauded to the dug-out by United fans "Once you are not a danger any more, people love you", he said and received a vase from Ferguson before kickoff. I think we are nearly there, but I can't celebrate because nearly is not enough.
"It was just another game for me but I'm very grateful for the gesture from Manchester United". But perhaps, in time, he will recognise the way its closing stages mirrored how his games at this stadium have always been: full of drama.
As for the reaction of his young but eager side, he added: "The players are destroyed because they gave everything and were caught in the final minute".
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Twitter last week reported its second consecutive quarterly profit, boosting the outlook for the platform after years in the red. One source told Reuters said the number is "substantial" and that the passwords were exposed for "several months".
The Portuguese has his own turbulent history with Wenger but hopes his latest victory does not mark the end of their tussles together. "I hope I play against him again".
Kanu won two Premier League titles, two FA Cups and a Community Shield during his time with the Gunners.
"I don't know where I will be. He was not on the list", said Wenger.
After almost 22 years with the north Londoners, his claims about wanting to take a break from the game appear to be genuine. "I would be surprised if I meet him next year".