Mata joined Chelsea from Valencia in 2011 and many wondered how he'd settle in England, given his sleight frame.
The Spain international ended up a key part of their Champions League winning campaign in his debut season and would win the Europa League a year later.
In that second campaign, he scored 19 goals and provided an astonishing 35 assists in all competitions.
Came to Man Utd at 25 and still i can’t explain what we did to him. Where did his career just go, he was meant to be a PL all timer. pic.twitter.com/GObIYkMjd0— 𝗧𝗲𝗻 𝗛𝗮𝗴’𝘀 𝗥𝗲𝗱𝘀 ✍🏼🇳🇱 (@TenHagBalI) April 25, 2022
Mata was their most valuable player ahead of Frank Lampard as well as that season's new recruits, Oscar and Eden Hazard.
Roberto Di Matteo was sacked and replaced with Rafa Benitez on an interim basis but it didn't slow Mata down.
What did, was the appointment of Jose Mourinho in the summer of 2013.
Mourinho didn't fancy Mata and let him join Manchester United for a then club-record £37 million in January 2014.
He's been at United ever since and despite being an experienced character in the dressing room, he's been on the fringes for a number of years.
Mata's regularly been played on the right wing rather than an attacking midfielder at Old Trafford, which isn't the best use of his skillset.
The 33-year-old will go down as a great player, but supporters believe he was destined for something legendary.
One commented: "Juan Mata is the only player post Fergie I’ll agree United truly wasted."
Another said: "No way was he 25, are you being serious..."
A third put: "United bought him as the best 10 in the league, played him nothing but RW and ruined his career. Low-key biggest football tragedy in years."
While someone tweeted: "We failed the nicest guy in football."
It's expected Mata will leave United in the summer when his contract expires.
He's made eight appearances in a bitterly disappointing year for the Red Devils and they'll likely finish outside the top four.
Incredibly, Mata has only played for United 21 times in the Champions League after winning the competition with Chelsea.
A reminder of how far they've fallen and how many of their players are missing out on Europe's elite competition.
Featured Image Credit: LS Comps/Twitter
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