4th January 2017. By Ryan Baldi.
As he whipped the ball into the corner of the West Ham United goal following a superb cutback from Marcus Rashford, for the second time in as many days, Juan Mata had come off the bench to set Manchester United on their way to another three Premier League points on Monday evening.


Against Middlesbrough at Old Trafford two days earlier, the Red Devils were growing frustrated at being on the wrong end of some questionable refereeing decisions by Lee Mason, while the visitors took a shock second half lead.


Anthony Martial drew United level with five minutes to play, before Mata picked out Paul Pogba inside the penalty area for the Frenchman to head in a late winner. The Spaniard's introduction after 64 minutes added a degree of incision that had been missing from their performance up until that point, and the same was true at the London Stadium.


Although Henrikh Mkhitaryan's recent superlative form has kept him on the sidelines of late, Mata remains a key player for United and has consistently performed to a high level this season, even when Jose Mourinho's men were struggling through September and October.


It was to the surprise of many that Mata was even a member of the Manchester United squad at all as the season began. After being named Chelsea's player of the year in each of his first two campaigns at Stamford Bridge, the 41-cap Spain international found himself warming the bench as a seldom-used substitute when Mourinho began his second reign in West London as the 2013-14 season began, and was sold to United for a then-club record £37.1 million in that term's January transfer window.


So when Mourinho was confirmed as the successor to Louis van Gaal at Old Trafford in June this year, one of the first thoughts on many fans' minds was that the arrival of the "Special One" would surely spell curtains for Mata's United career.


Throughout the summer, speculation was rife that the 28-year-old was set for a move away from Manchester, with Everton and Juventus tipped as potential suitors.


And when he was brought on as a second half substitute in the Community Shield against Leicester City in August, only for Mourinho to then substitute him for Mkhitaryan in the closing stages, obituaries for the player's Old Trafford tenure were already being written.


The Portuguese tactician insisted that, with the Red Devils clinging to a narrow lead, Mata's removal was a safety measure aimed to equip the FA Cup holders against last-ditch aerial attacks, and was in no way a personal slight.


But nobody was buying it. The move was seen as a Machiavellian boss aiming to deliberately undermine a player he wanted rid of; Mata would almost certainly be gone before the transfer window closed, or else he'd face four months in the wilderness - just as he had under Mourinho at Chelsea -before finding a new club in January.


That narrative failed to materialise, though: Mata started the very next game and even scored, helping Mourinho's men beat Bournemouth 3-1 at the Vitality Stadium.


That was the first of 17 starts in all competitions so far this season, with 23 appearances in total. In that time Mata has contributed six goals and two assists, including vital strikes against Arsenal, Bournemouth and West Ham in the Premier League, and Manchester City in the League Cup.


With a pass accuracy of 91 percent this term, Mata's quality has been evident whenever he has taken to the field. Reliable in possession, he is also arguably United's most creative player; when a resolute backline need unlocking, Mata invariable appears with his skeleton key.


Of the Red Devils' vastly talented roster, only Zlatan Ibrahimovic and Paul Pogba can better Mata's tally of 24 chances created in league action this season, while his 77 percent shot accuracy is better than any United player to have taken more than one shot at goal.


Mata's creative powers have never been in question. Since he moved to Old Trafford three years ago, he has been directly involved in 40 league goals (25 goals, 15 assists) in 101 games. And among that tally their have been decisive strikes and moments of inspiration in big games, such as his superb brace at Anfield in March 2015 and a late equaliser against Crystal Palace in last season's FA Cup final at Wembley.


The one recurring knock on Mata's skill set is a perceived lack of physicality and an inability to adequately carry out his defensive duties. But this season, of all the United midfielders, only Michael Carrick can better the former Valencia playmaker's percentage of duels won (54 percent).


During his time in Manchester, Mata has shown a willingness to adapt. If you were to ask him to identify his favoured position, he'd likely be too polite to choose, but there is no doubt that he sees himself as a classic No. 10, operating in the central zone between the midfield and striker(s).


But, either under van Gaal or Mourinho, whenever a 4-2-3-1 formation has been used, others have tended to be picked ahead of Mata in the central attacking midfield berth, with, rightly or wrongly, Wayne Rooney often being the preferred option in that role.


And when, as has been the case in recent weeks, the Red Devils line up in a 4-3-3 formation, there is no No. 10 role as such, with one of the deeper midfielders - namely Pogba - given licence to break into the zone where an advanced playmaker would usually operate.


So Mata has had to content himself with a role on the right of United's attack. With his slight frame and lack of pace, the Spanish star would not necessarily be an obvious choice for this position, but he has learnt to make it his own, choosing to drift inside onto his favoured left foot, creating space for Antonio Valencia to push forward from right-back.


And although he would probably prefer to play centrally, Mata just seems genuinely delighted to be playing and representing one of the biggest clubs in the world. His application and dedication to the cause is beyond question.


Ever the professional, the ex-Real Madrid youth teamer is not one to sulk when another of his gifted attacking colleagues are selected ahead of him. Instead, the studious and analytical Mata intently watches the game from his position on the bench and equips himself to make an impact should he be called upon.


Through his skill, temperament and professionalism, Mata has convinced Mourinho of his worth to United, and remains a key player in the Red Devils recovery.