Dundee United teenager Ryan Gauld has signed for Sporting Lisbon on a six-year deal that includes a reported £48 million (60 million euros) buy-out clause.

The 18-year-old midfielder is moving to Portugal in a deal worth £3m, according to the BBC, after being dubbed 'Mini Messi', in tribute to Argentina's Lionel Messi, by his Tannadice team-mates while scoring eight goals in 38 games last season for Scottish Premiership side United.

Now though the Scotland Under-21 international, long tauted as the one of the country's best football prospects, will find himself joining a Sporting club responsible for producing Figo and Cristiano Ronaldo.

Gault will also have a chance to take his game to a new level as the 18-times Portuguese champions have also qualified for next season's Champions League.

"Everyone at the club wishes Ryan sincere best wishes in his future career," said a United statement.

Comparisons between the 5ft 6in Aberdeen-born Gault and the equally diminutive Messi started to emerge on the back of the teenager's impressive displays last term.

Speaking in December, United boss Jackie McNamara, who won 33 caps for Scotland, said: "He's going to be a massive star in our national team, there's no doubt about that. He will be one of the greats of our game."

Gault made his United debut in 2012 and was a key figure as the club finished fourth in the Premiership last season and runners-up in the Scottish Cup.