Sanchez is currently in the last six months of his deal with the Gunners, and a deal to sign for United is edging closer by the day. If the deal does go through it would once again show that Arsenal sell their best players to their rivals, much like when they sold Van Persie to United back in 2012 and in that season the Dutchman effectively won the league for the Red Devils.
Speaking about the departure of Sanchez, Wenger admitted that the potential incoming of Henrikh Mkhitaryan to the Emirates has somewhat made the whole Sanchez transfer a bit easier for the fans and added that the sale of the Chilean will not be less hard felt than the sale of Van Persie.
“I would say our fans know Alexis will not extend his contract and they have accepted that idea – and the fact it will not be one-way traffic it will be other way traffic as well and so that makes the whole thing a bit smoother, maybe. A bit less disappointing", as quoted by the Mirror.
“We took Van Persie when he played in the reserve team at Feyenoord. We made a long work with him. When you get them there and, after they leave, that is the most painful", as quoted by the Telegraph.
For the Arsenal fans, the move for Sanchez will not be as painful as Van Persie's exit, but it will still hurt a bit as once again one of their star men departs to another rival club.
The Gunners have built this reputation of building up players and then selling them on for a profit, much like German side Borussia Dortmund - which now brands Arsenal as a selling club. The possible incoming of Mkhitaryan could be a success, but losing a player like Sanchez to United is simply unacceptable.
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As for Arsenal, they host Crystal Palace at home on Saturday, and they are likely to be without their Chilean star as he looks to finalize his deal to the Red Devils. A win for the Gunners is a must against the Eagles if they are to keep their slim hopes of finishing in the top four alive.