The chair of the Arsenal Independent Supporters Association has urged fans to rally behind the players.
AISA chair Lois Langton told PA Sport: "To say it was a night to forget is an understatement. There isn't really any gloss to put on what was an abject performance. The only positive we can take going into the second leg is that we can't play that badly again.
"I would like to think we didn't take Monaco lightly and view them as an easy tie after recent draws at this stage of the competition. If we did, it backfired spectacularly. Monaco relied on disciplined team work to perfection.
"However, the tie is still not beyond us.
"We so nearly pulled back a 3-1 home defeat against Bayern Munich in 2013, eventually only going out on away goals when all the pundits had already written us off.
"You would hope that last night's result will provide the proverbial wake-up call and the team will produce the sort of collective attacking display of which we are capable - and that this time we will get the extra goal needed to put us through.
"Also, now is not the time to criticise the players, because the team and supporters need to believe that we can overturn the deficit."
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