Emi Martinez admits he is "devastated" by the injury to Bernd Leno in our defeat to Brighton on Saturday.
The Argentinean stopper came on to replace his goalkeeping colleague in the first half, and says it was a tough situation for everyone.
"In the goalkeepers' union, you don't want the other goalies to get injured because it can happen to anyone," Martinez told Arsenal.com.
"We train every day together, we support each other, we're really close, we even have a WhatsApp group for just me, Bernd and Matt - it is devastating to be honest.
"I wish him a speedy recovery and if he needs the rest of the season, me and Matt will try to do a good job in the Premier League and try to cover him as much possible.