Sanchez takes aim at his critics as he says his Arsenal goodbyes

Alexis Sanchez paid tribute to Arsenal's fans, players and staff after completing his anticipated switch to Manchester United - but admitted criticism from some former Gunners had left a bitter taste.

The Chile international, who has moved to Old Trafford in a swap deal that sees Henrikh Mkhitaryan head in the opposite direction, used his personal Instagram account to declare his appreciation for those he'd "shared many nice things for the club" during his time at the Emirates Stadium.

However, Sanchez also made a point of reacting to those ex-players who had questioned his attitude during the final stages of his career at Arsenal.

The 29-year-old forward - heavily linked with a switch to United's neighbours Manchester City in the previous transfer window - insisted he remained fully committed to his previous employers despite speculation over his future.

"There are people [former club players] who have spoken with no knowledge of what happens inside the club and cause damage," Sanchez wrote.

"I must say I always gave 100 per cent, until the last day, when I asked to the Mister [Arsenal manager Arsene Wenger] to be in the team, because I wanted to be a contributor."

Arsenal decided to go ahead with the swap deal rather than allow the player's contract, which would have expired in June, to run down, negating the risk of losing him for nothing.

Sanchez had joined them from Barcelona in 2014 and won the FA Cup twice during his time with the London club, scoring in final victories over Aston Villa in 2015 and Chelsea last season.

He scored 60 goals in 122 Premier League appearances for Arsenal but will now wear the famous number seven shirt for their Premier League rivals.

"Thanks for everything Gunners! All we achieved and the good moments that I gave to the club, I want to dedicate it to the fans, they are the most important. Thanks for every time you sing Alexis Sanchez Baby," he signed off the video post.