Alexis Sanchez has already made it clear who he's supporting in Arsenal vs Manchester United

Alexis Sanchez looked like one of the best players in the world during his time at Arsenal, although things didn't really work out for him once he made the switch to Premier League rivals Manchester United.

The Chilean netted 80 goals and bagged 45 assists during his time at the Gunners, but managed to find the back of the net just five times, setting up his teammates on nine occasions for United. Sanchez' time at Old Trafford was shortlived as he failed to justify being given the iconic No.7 shirt and he moved to Inter Milan just a year-and-a-half after signing for the Reds.

The forward's time in London, however, was rather different. Sanchez enjoyed three-and-a-half successful years at the Emirates Stadium, winning two FA Cups with Arsenal.

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That, perhaps explains Sanchez' previous comments that Arsenal 'will always be in my heart' ahead of the two sides' last competitive encounter. In the build-up to the game in January, Arsenal's social media accounts had been re-living some of their favourite goals against Sunday's opponents, with Sanchez's superb strike in a 2015 3-0 win spotted by the Chile international.

"You remembered me. I will never forget you too," Sanchez wrote in response to the Instagram post. "You will always be in my heart. You were my first family in England. And everyone took good care of me especially the fans. All the best Gunners."

Arsenal would end up winning that game as Eddie Nketiah flicked home a late winner in a five-goal thriller, with Marcus Rashford and Lisandro Martinez getting on the scoresheet for United.

Sanchez's previously admitted regretting swapping north London for Manchester. "Sometimes there are things