The 28-year-old has enjoyed an outstanding season for the Gunners with 16 goals in all competitions.
But with 18 months left on his current contract, his future at the Emirates is far from certain.
Alexis Sanchez furious after being substituted against Swansea
Sat, January 14, 2017
Alexis Sanchez was not happy to be subbed off during Arsenal's win over Swansea
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Alexis Sanchez scored during Arsenal's win over Swansea
Earlier today Arsenal boss Arsene Wenger said there was no update on the negotiations between club and player.
And last week, the Chilean was visibly displeased to be taken off in the 4-0 win over Swansea.
Alexis Sanchez has been in excellent form for Arsenal
But ahead of this weekend's clash with Burnley, Sanchez posted an image of himself smiling during Arsenal training on Instagram.
In the caption, translated to English from Spanish, Sanchez said: "Strong people smile with a broken heart, they cry with the doors closed and fight battles that nobody knows."
A photo posted by Alexis Sanchez (@alexis_officia1) on
It is unclear what battles Sanchez may be having in his life.
But he will be cheered by Arsenal fans' efforts to raise £500 to produce banner tributes for his dogs Atom and Humber.
Within 24 hours the target set by fan group REDaction was reached and the banners are set to be on display inside the Emirates Stadium on Sunday.