Montpellier midfielder Younes Belhanda fears the out-of-sorts French club could concede eight goals against Arsenal in the Champions League on Tuesday.
The reigning Ligue 1 champions have taken just four points from five games this season and suffered their third defeat of the campaign when they lost 3-1 at newly-promoted Reims on Friday.
Arsenal destroyed Southampton 6-1 in the Premier League on Saturday, and Belhanda believes Montpellier must quickly rediscover their form and mental toughness if they are to avoid humiliation at the Stade de la Mosson.
"If we play like this, we're going to concede eight," Belhanda said. "We have to show as quickly as possible that we are men, because we look like kids on the pitch. We're not dangerous, not sharp enough."
Montpellier coach Rene Girard has said he does not recognise the players that won the title last season and believes his team may have been over-confident before the start of the campaign.
"We should be ashamed of ourselves", he said after the Reims defeat. "For the first time, I am asking a lot of questions of myself. They [the players] have forgotten some values."