Arsenal welcome Barcelona to north London for the first leg of their Champions League last-16 tie against the Spanish champions and are the heavy underdogs heading into the game.
Sanchez scored 39 La Liga goals for Barcelona during his spell at the Camp Nou between 2011 and 2014, before his big-money transfer to Arsenal.
And Sanchez used his personal Instagram account to send a message to his former club and also underline his commitment to Arsenal.
Sanchez posted the picture above on Tuesday morning and wrote: “I want to thank FCB, the doctors and the physiotherapists who cared for me during my stay in Barcelona and especially the players with whom I shared beautiful moments.
“But life carries on and my present is with Arsenal, my home, my family and I’m so happy to be a Gunner.”
Arsenal head into the last 16 tie looking to progress to the quarter-finals of Europe’s elite club competition for the first time since 2010.
Sanchez has recently made his return to action after a lay-off with a hamstring injury.
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