Just how good is Ander Herrera? It’s a question that many followers of Spanish football – not just Manchester United fans – are intrigued to have fully answered.

For a long time now, Herrera has looked more than capable of becoming a truly outstanding performer, good enough to establish a regular place in Spain’s international squad if not the starting 11.

However, the fact that he has still not been called up by Vicente del Bosque, while lesser regarded midfielders such as Mario Suarez, Javi Garcia and Herrera’s Athletic Bilbao team-mate Ander Iturraspe have, makes it clear that the 24 year-old has not yet fulfilled his undoubted potential.

Three years ago, Herrera played an important role in Spain’s Under- 21 European Championship triumph, scoring twice including the opener in a 2-0 final victory over Switzerland.

That same summer, he also earned a dream move to his hometown club, Athletic Bilbao, having already impressed in the top flight with the lower-profile Real Zaragoza.

At that time, as a freshly crowned European champion and a new signing for arguably Spain’s most popular club outside the Big Two, Herrera’s future looked nothing but bright.

Since then, his progress has been…well, OK. He’s certainly not been a failure in Bilbao, maintaining a regular starting place throughout the last three seasons and playing a significant role in the team’s long-awaited return to the Champions League.

But he hasn’t set the world alight either, evidenced by the fact that Manchester United have hardly been forced to beat off a string of fellow admirers in order to secure his services.

To focus on the positives, it’s evident that Herrera possesses plenty of technical, physical and mental attributes. He is a hard worker who plays for the team rather than himself, has great energy to cover plenty of turf and is easily quick and strong enough to cope with the unique demands of the English Premier League.

Furthermore, Herrera is also technically adept, with a good first touch and a wide range of passing. He makes well-timed runs into the penalty area to attack crosses, and is always looking to be positive in possession.

However, although numbers can be misleading, Herrera’s stats from his time in Bilbao are less than overwhelming. He scored only seven goals in nearly 100 league appearances and for a player whose role in the team was to provide the link between midfield and attack, 14 assists in three seasons were also respectable rather than spectacular.

Maybe this move is just what he needs and his talents will only really come to the fore when he’s surrounded by better players: history contains plenty of examples of players who have only really flourished when they step up to a bigger stage.

United fans should hope that happens with Ander Herrera because although he is clearly a good player with the potential to become a very good one, on the evidence presented so far, €36 million (Dh179.9m) looks to be the upper limit of his value.