That’s according to European football expert Gabriele Marcotti.
Arsenal star Sanchez wanted to join Manchester City this summer, with Pep Guardiola keen to reunite with the former Barcelona star.
However, the Gunners couldn’t find a replacement for the Chile international, despite making a deadline day bid for Monaco sensation Thomas Lemar.
Liverpool’s Coutinho handed in a transfer request to force through a move to Barca, while Chelsea striker Costa wants to return to Atletico Madrid and has currently gone AWOL.
The Spain international, who was told to leave Stamford Bridge by Antonio Conte, is in Brazil and refusing to return to Chelsea training.
And Marcotti says Sanchez is the most bothered out of the trio about not getting his summer transfer.
“Yeah he [Costa] is getting fined and they’re obviously mounting up,” Marcotti said on ESPN FC.
“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.
“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.
“I also get the sense Alexis, dare I say this, cares more than perhaps the other two guys.”
