Alexis Sanchez is in the final year of his contract at Arsenal and has so far rejected a new offer from his club so far.
The Arsenal star was also pursued by Manchester City during the summer transfer window for £60 million but the negotiations failed to see through.
City are expected to prise the 28-year-old star again in January when the transfer window opens and this time, whoever gets the star will be able to transfer him for free as his contract ends this year.
Jose Mourinho is also reported to be interested in Sanchez so it looks like City will have a big competition comes the January transfer window.
While Sanchez will be available on a free transfer, United may pay a signing-on fee amounting to £25 million just to secure his signature.
If Arsene Wenger cannot convince Sanchez to sign a new contract with them before his contract ends, this will be a huge blow for the club as they do not have a replacement for him just yet.