Alexis Sanchez regretted his move to Manchester United after just one training session and was already considering a return to Arsenal.
The Gunners are set to host United at the Emirates Stadium on Sunday, aiming to eliminate the FA Cup holders from the competition immediately.
Sanchez is among a select group of players who have represented both clubs, though his experiences at each were markedly different.
The dynamic Chilean forward arrived in England in 2014, transferring to Arsenal from Barcelona, where he quickly hit his stride.
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