The Chile international’s future was a relentless source of speculation throughout the summer transfer window after he entered into the final 12 months of his contract at The Emirates.
Sanchez, 28, was heavily linked with a move to Manchester City in the closing few days of the summer transfer window, but a switch failed to materialise for the forward.
The attacker will now have to focus on Arsenal until January at the earliest as he looks to help the Gunners bounce back from their poor start to the season.
However, he won’t be happy about his current situation and is more upset than his Liverpool and Chelsea counterparts at not securing a transfer, according to journalist Marcotti.
Marcotti told ESPN FC: “He (Costa) is getting fined and they’re obviously mounting up.
“In the end, if he moves in January he may not end up paying it, it may come out of his new club or whatever.
“To me there’s no question Alexis is going to be the guy who’s least happy this year.
“Philippe Coutinho’s going to buckle down, he’s going to work hard and he’s going to make his way back into the team.
“Klopp will welcome him back and he’s got a World Cup with Brazil to look forward too. Diego Costa we’ve covered.
“Alexis Sanchez is stuck at Arsenal, he’s going to play every minute and whatever he does on the pitch, he’s going to get scrutinised.
“’Oh his body language is wrong, oh look at this’.
“I think out of the three the guy I feel for the most is Alexis Sanchez.
“I also get the sense Alexis, dare I say this, cares more than perhaps the other two guys.”
Sanchez will be expected to feature for Arsenal when the Gunners return to Premier League action on Saturday afternoon with a home clash against Bournemouth at The Emirates.
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