(CNN) At the tender age of just 19, Joao Felix is already breaking records, not to mention attracting admiring glances from Europe's biggest clubs and comparisons to some of Portugal's greatest players.

The Benfica forward became the youngest player to score a hat-trick in the Europa League when the Portuguese league leaders defeated Eintracht Frankfurt 4-2 in the first leg of their quarterfinal tie in Lisbon (although they would subsequently lose the tie on aggregate).

On Monday, he grabbed a brace against Maritimo in the Primeira Liga, while a long list of suitors -- which is reported to include Juventus, Real Madrid, Manchester City and Manchester United -- are said to be tracking his performances, with Benfica reportedly having inserted a $135 million release clause in the teenager's contract.

Not bad for a player that only made his competitive first team debut last August.

For those who have worked with Felix from an early age, however, his rapid progress comes as no great surprise.

"He's a very talented player, very technical player," Joao Tralhao, who coached Felix in the Benfica youth ranks before moving to become assistant to Thierry Henry during the Frenchman's spell as manager at Monaco, told CNN Sport. "(Felix's) decision making qualities are absolutely amazing, outstanding. Elite level for sure," Tralhao adds.

Tralhao says Felix was long a standout during training games with Benfica's senior squad when he was still a youth team player, marking out his clear potential.

But talent does not always equal progress and the fact that he is "very humble, likes to work, likes to listen ... (and) has a competitive mentality" has aided his progress, Tralhao adds.

Different from Ronaldo

Tall but graceful, Felix is strong in the air and skilful with the ball at his feet.

His exquisite balance, vision and languid running style have earned comparisons to former Brazil international, Kaka, as well as Benfica stalwarts such as Rui Costa.

Thirteen goals in 22 league appearances this season, meanwhile, puts Felix among the top scorers in the Portuguese top flight -- an impressive return for a player so young, not to mention one that does not always play as an out-and-out striker.

He appeared emotional after scoring his third goal against Frankfurt, further endearing him to Benfica fans who quickly took to the teen after he scored against arch-rivals Sporting in one of his first games.

And Felix brought yet more smiles when he scored against Maritimo, hugging his younger brother who was positioned behind the goal and working as a ball-boy.

Joao Felix reacts after scoring against Eintracht Frankfurt.

Being Portuguese Felix has, perhaps inevitably, been labeled by some as the next Cristiano Ronaldo.

The teenager has spoken of his admiration for Ronaldo in the past, telling Spain's Marca he was an "exemplary footballer" and the "best in the world."

For Nuno Gomes, a former Benfica player and 79-cap international for Portugal, however, such comparisons are not entirely fair.

"They are different," Gomes says of the two players. Ronaldo is the best in the world, aged 34. Felix is still only 19."

Cristiano Ronaldo (R) Joao Felix train for the Portugal national team.

Gomes became the general manager of Benfica's youth department shortly after Felix was signed from rivals Porto's youth ranks. He has watched his development closely and offered him a first professional contract at the age of 16.

Reports suggest that Porto were unsure about Felix when he was there given his slender frame.

But Gomes says Benfica were quickly convinced by his potential once he began to work with the club's coaches. "It was clear for everybody that we were in front of a young special talent," he says.

"His relationship with the ball, his first touch, his intelligence" marked him out as a completely "different kind of player."

Joao Felix is pictured playing for Benfica.

'He is already a star'

Porto's loss is certainly Benfica's gain.

They not only have an outstanding talent, potentially helping them towards the latter stages of the Europa League, but an asset Europe's richest clubs look set to battle it out for the right to buy.

Benfica has traditionally produced some of the most exciting, young Portuguese players. It has also developed a reputation for signing and developing talented individuals from outside Portugal before selling them on to clubs in Europe's biggest leagues at a profit.

Recent big money sales include Ederson, David Luiz, Nemanja Matic, Victor Lindelof and Angel Di Maria. Bernardo Silva, Renato Sanches and Joao Cancelo also came through the ranks at Benfica.

That model suggests Felix will also be sold in future too.

Joao Felix (R) celebrates with his Benfica teammates.

Both Gomes and Tralhao see Felix signing for one Europe's biggest clubs for a considerable sum of money one day.

Gomes played in Serie A for Fiorentina, as well as Blackburn Rovers in England's Premier League, and says it will be important that Felix keeps his feet on the ground in the months and years ahead.

He adds that Felix -- who he describes as "reserved" and an often quite "shy" individual, but one who can also be extremely "funny" -- has the intelligence, character and support of a strong family not to get carried away.

"Even if he is a star already, he is a young boy that has humility, he's a nice guy, he's a nice person," Gomes says.

Tralhao concurs and says that although football will "create obstacles," his former youth player has the intelligence to navigate them.

In the meantime, Benfica will hope to reap the benefit of Felix's cleverness and ability on the park.

While the Europa League may now be out of the question after being eliminated by Frankfurt, the battle with Porto for the Primeira Liga title remains very much on.