The Chilean was dropped by Arsene Wenger for Saturday's 3-1 defeat to Liverpool but returned to the starting line-up in last night's humiliating 5-1 loss to Bayern Munich.
Wenger insisted there was no incident but Robert Pires confirmed Sanchez had stormed off the pitch after a heavy tackle.
Second Arsenal player spotted laughing during Bayern Munich clash
Wed, March 8, 2017
Click to reveal the second Arsenal player spotted laughing during defeat against Bayern Munich
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Click to reveal the second Arsenal player laughing during Bayern Munich defeat
And Walcott says the Arsenal players have to stick together to rescue their faltering season.
“Things get taken out of proportion — we all know this,” Walcott told the Evening Standard.
Theo Walcott wants his Arsenal team-mates to refocus
“There are certain things that happen at training grounds.
“I’m sure it happens at every other training ground, most of the time, really.
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Alexis Sanchez was named as a substitute against Liverpool
“You don’t see it often at Arsenal. Things have happened. They need to stay in the dressing room and the players and staff need to sort it out. We are in it together here. We can’t be fighting each other.
“I don’t really want to go into it but the stuff that has gone on did not affect our first half here. At certain times when things don’t go well, you don’t want to have anything in your head that you are giving up.