Lionel Messi and Ryan Gauld have more in common than their size

Being exceptional has become commonplace for 18-year-old Ryan Gauld.

There has barely been a moment in his short career when he has not been set apart from his peers, so a move to Sporting Lisbon for around £3m will not faze him.

At seven, he was so technically accomplished that during a training drill his Brechin City youth coach asked him to demonstrate to the rest of the team how particular skills should be performed.

Once he switched to United - along with every other member of that Brechin youth team - he was quickly moved up the age groups, turning out for the under-19s while he was only 16.

Ian Cathro

To develop players with imagination and creativity, kids need to be allowed to make mistakes but we don't give them the opportunity to express themselves

Ian Cathro, former Dundee United youth coach and Gauld's mentor

Even his appearance was eye-catching, because Gauld was so much smaller and slighter than his contemporaries. His stature contributed to him being called 'Mini Messi', and the nickname was apt given his talent.

Scottish football is still occasionally inclined to prefer physical attributes over technique, but Gauld's talent was always clear to see.

His first match for United's under-19 side was watched by the Scotland under-21 manager Billy Stark, who within 12 months was calling the player up to his squad.

The ability was evident, and his progress gathered momentum when he turned 16. By then, opponents struggled to contain Gauld. His low centre of gravity contributed to his evasiveness, as did a sharp turn of pace, but the significant quality was his ability on the ball.

His talent was natural, but also honed. Gauld came under the tutelage of Ian Cathro, who revamped United's youth set-up so that it focused on developing ball skills and fast-tracking young talent up the age groups.

Gauld, along with his Brechin youth team-mates John Souttar and Euan Spark, were among the first to benefit from Cathro's approach, which was not typical to Scottish football.

"We don't allow players to be technically brilliant in this country," Cathro once observed. 

"To develop players with imagination and creativity, kids need to be allowed to make mistakes, but we don't give them the opportunity to express themselves. We'd rather prescribe what they do."

Cathro never played the game professionally and turned to coaching in his early 20s.

It was only when then United manager, Craig Levein, was struck by the quality of the youngsters Cathro was working with as an independent coach that he offered him a role at Tannadice.

Cathro ensured Gauld spent hours working on his awareness, so that he was thinking two or three passes ahead and not just on his immediate delivery of the ball.

Ryan Gauld has shown his undoubted talent during a remarkable rise to prominence at Dundee United

Gauld provided the assist for each of United's goals in their 4-1 win over Partick Thistle in November

The coach's influence remained even after he left Tannadice. Cathro is still close to Gauld and his own move to become assistant head coach at Portuguese side Rio Ave confirmed the notion in the teenager's mind that his career might be best served by leaving the UK.

Adjustments will need to be made, since footballers in Europe are still more inclined to ensure that their professionalism impacts on every aspect of their life. There is less of a drinking culture, a more committed approach to fitness, diet and training, and coaching sessions tend to last longer than in the UK.

The Portuguese game may be more suitable to Gauld, though, since the play tends to be less hectic and intense. Players dwell on the ball and attacks are more considered. Sporting Lisbon will also be the ideal environment for him to develop further.

The club has based its recruitment strategy on signing young players - often for around the £3m they reportedly spent on Gauld - on the basis that while some will not make it into the first team, the investments will be covered by the ones who do and are sold on at a profit.

Who is Ryan Gauld?

Born 16 December, 1995

Debut v Motherwell on 13 May, 2012

First goal v St Johnstone on 1 April, 2013

Career stats 32 starts, 18 substitute appearances, nine goals

Gauld may not feature in the Sporting first-team in his debut season, but he has signed a six-year contract and the move is about influencing the overall direction of his career. He is a mature young man, and some in the game in Scotland have remarked on the fact that he has the football brain of a man but the body of a young boy.

Gauld made a bright impact for United in the early months of last season, drawing scouts from all over Europe to Tannadice. There was shrewdness in the way manager Jackie McNamara sent Gauld and Souttar on holiday during the winter transfer window to shield them from the speculation about their futures.

Both are grounded, but their form diminished as the season drew to a close. Neither, for instance, started the Scottish Cup Final defeat by St Johnstone, although Gauld did make an appearance off the bench.

An astute, composed young man with a wonderfully instinctive touch on the ball and a perceptive passing ability, Gauld is not a typical product of Scottish football.

Sporting Lisbon are the next beneficiaries of his talent, but his success is also a reminder to the game he has left behind that skill and ability are more valuable than physical stature.

Watch Gauld providing the assists  for each of Dundee United's goals in their 4-1 win over Partick Thistle in November.