The Chile international was powerless to prevent the Gunners losing 4-3 to Liverpool at the Emirates Stadium in their Premier League opener on Sunday afternoon.
Sanchez couldn’t get on the net as Theo Walcott, Alex Oxlade-Chamberlain and Theo Walcott scored for Arsene Wenger’s side but it wasn’t enough to rescue a point.
The South American enjoyed a successful summer as Chile won their second successive Copa America title following a penalty shootout victory over Argentina.
And Sanchez looked in high spirits as he posed for a selfie with his golden retrievers Atom and Humber which he posted on his Instagram page on Thursday evening.
Sanchez moved to Arsenal in a £35m deal from La Liga giants Barcelona following the World Cup in Brazil in 2014.
The Chile international has netted 42 times in 93 appearances in all competitions over the past two seasons.
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