One of the most impressive young players in La Liga in the 2015-16 season was also one of the most interesting to watch from a tactical perspective: Saul Niguez, Atletico Madrid's enormously talented 21-year-old midfielder.
Despite winning the Revelation of La Liga award for his performances over the campaign, and establishing himself in Diego Simeone's team to the extent of being a guaranteed starter as the team reached the UEFA Champions League final, Saul just missed out on a place in Spain's UEFA Euro 2016 squad after being cut from the final 23.
Talent aside, that decision was perhaps more surprising given one of Saul's biggest traits: a versatility matched by very few, certainly within Spain's current group, that could have proven invaluable at a tournament.
Nonetheless, he has a huge future at club and country level ahead of him, and the past seven months have shown exactly why.
1 man, 7 roles
A bit-part player in midfield during 2014-15, Saul's adaptability had already been on show when he starred in central defence as well as in midfield for Rayo Vallecano in 13-14 as a teenager on loan.
It was in November of the 15-16 season when he really made the breakthrough as a regular starter for Atletico, though, playing in the centre of the park or from the right flank in a 4-4-2 as need determined.
Over the course of the entire campaign, he showed his remarkable versatility by appearing in five positions and no less than seven roles for Atletico: centre-back in an emergency once, sole striker late in a game once and all the way across midfield, right, left and centre.
In central midfield, he has played every role imaginable; from the deepest-sat defensive shield, through to a box-to-box role and all the way to playing as a barraging, lung-bursting No. 10 support forward.
He has the physical capacity to perform any of them in both offensive and defensive capacity, the technical traits to be an assured success in possession anywhere on the pitch, and the mental resilience that comes as a built-in standard for players coming through Atleti's cantera and training under the tutelage of Simeone.
Surging from central
Since most of Saul's time has been spent centrally in one capacity or another, we'll start there—but it's worth noting that in the starting XI, Saul is roughly evenly split between being named as a central midfielder and one of the two wide starters. The game time leans more heavily central though, as Simeone often alters his shape in-game to move to a 4-3-3, with Saul inevitably one of those switching infield.
At 21, he no doubt still has a little physical growth left in him, but Saul is already powerfully built, has good acceleration and can run for days—he regularly tops the distance-covered charts in matches, including the Madrid derby last term (via Marca), covering more than 13 kilometres in the 90 minutes.
When paired with Gabi in a two, or else used as one of the No. 8s in a three-man midfield with Gabi or Augusto Fernandez at the base, Saul's physical prowess comes to the fore.
He is able to shuttle sideways to help the team keep shape and win possession, but he will then be one of the two or three players who immediately drive on forwards, supporting the attackers from the second line in midfield and looking to receive possession on the run.
In doing that, his technical traits are also seen: a great first touch, the individual skill to take players on and a willingness to run beyond the forward and force shots or close-range cut-backs for team-mates.
Saul's tactical awareness is sufficiently developed already that he rarely gets caught ahead of play and out of position. When playing centrally he is fundamentally a ball-winner, but his capacity for breaking opposition lines with passes or with runs to exploit space is a key aspect of his game.
Roaming from wide
Atletico play a 4-4-2 with frequency, but it's nothing like a winger-heavy, play-it-wide-and-cross approach that the system is still associated with.
Inverted wide midfielders sees Saul and Koke as two of the most frequent starters: Saul right side, Koke left, both sitting narrow in the channels rather than the wings and looking to squeeze out space in the centre, forcing opponents backward or sideways.
Both players then come infield when in possession, on their stronger foot (Koke right foot, Saul left) and opening their field of vision to everything across the entire width, rather than just directly ahead down the flank.
Indeed, when Saul doesn't have the ball, he still looks to move along the channel, picking spaces between the lines to take possession in or else, if play develops on the opposite flank, surging forward to attack the far post and run beyond the striker if necessary.
That latter point is such an underrated and overlooked aspect of midfielders that, if he continues to make it an ongoing characteristic of his, it will make him one of the game's biggest stars.
He gets into tremendous goalscoring positions on account of his willingness to break so far upfield, and Atletico have already benefited from it on plenty of occasions. It's no coincidence he was the highest-scoring midfielder in the squad, hitting nine over the season.
His dribbling and close control was a point many took away as a marker of Saul's ability after that goal against Bayern Munich in the Champions League, but it's just one small part of an all-round, remarkably complete midfielder.
Where does he go from here? Where is Saul's best role now, and where will it turn out to be two or three seasons down the line? We can look to team-mate Koke as an example: He continues to feature from the left in Atletico's 4-4-2 but plays centrally for the national team. That's more than likely the path Saul will tread, too.
His versatility is not seen as a negative aspect in Spain as it can be sometimes in England—the dreaded "utility man" tag doesn't apply, he's simply another tool to alter tactics as necessary with slight tweaks rather than overhauls and substitutions.
That said, Atletico signing Nicolas Gaitan and looking for a new No. 9 hints at a change: Antoine Griezmann could be used more often as a wide forward from the start, pushing Atletico to a 4-3-3 and meaning more chances at the heart of the team for Saul.
Playing both he and Koke ahead of one defensive screen—Gabi the natural choice to start, Augusto Fernandez the alternate and Matias Kranevitter the hopeful long-term star—gives a tremendous balance of physicality, technicality and creative impetus to Atletico's midfield, while also retaining the ability to easily tilt back to a 4-4-2 when Griezmann stays high.
Saul will become seen as a central midfielder more and more often, and his attacking instincts cannot be denied. He will hold ground in the middle but must be allowed to continue surging as an attacking threat from deep—a true box-to-box player who can stop and score in equal measure.
Atletico have a rare talent on their hands, a complete midfielder who can dominate La Liga for years to come.