Luke O'Nien has yet to make his professional debut but the young Watford midfielder has already developed a reputation for being one of the club's hardest workers, purely by word of mouth.

O'Nien is often seen doing his own training when visiting the Hornets' London Colney training base and the 19-year-old has already won over new head coach Beppe Sannino.

Last week's pre-Manchester City interview with Sannino was interrupted when the Hornets' boss shouted across the room to O'Nien to tell him "Luke, you are number one.

"I like him. My dream is to give Luke the chance to play his first game as a professional," Sannino added.

O'Nien had been an unused substitute in the first two rounds of the Capital One Cup and a Championship game in November under Gianfranco Zola but has yet to make his professional debut.

The first-year pro was on the bench again for Sannino's second and third games in charge but had not been in the squad for the following three matches due to the arrival of Alexander Merkel and the return of Almen Abdi.

The above is indicative of the challenges Hemel Hempstead' O'Nien faces; coming up against the likes of former Swiss international Almen Abdi and ex-AC Milan midfielder Merkel.

But the likeable youngster, who joined Watford at under-nine level, is seemingly doing everything possible to earn an extension to his one-year contract before it expires in the summer.

Injuries and suspensions may have been a factor but Sannino was delighted to reward O'Nien with a place on the Golden Boys' bench at the Etihad Stadium against Manchester City.

"Luke O’Nien on Saturday was touching the sky," Sannino said. "I saw him playing with the ball before the warm-up and he looked like a happy child. I am happy for him."

Fellow academy graduate Sean Murray also acknowledged O'Nien's incredible work rate after the FA Cup tie.

He said: "Today will have been great for Luke and it is a reward for all of his hard work. You see him out there every day [doing extra training]; he has an unbelievable attitude and being involved in this kind of game is a great reward for him."

O'Nien has always been a good player from a technical point of view but he was smaller than most at youth level.

However, he has had a welcome growth spurt over the last 18 months and the creative midfielder has featured regularly at centre back for the Golden Boys during pre-season and in reserve and Under-21 games.

The Hornets were looking to loan out O'Nien earlier this season but Sannino was keen to keep the youngster at the club due to his attitude towards the club.

Earlier this month, Sannino explained: "When I joined this club the spirit of belonging to Watford was important for me, even though I’m not British.

"And Luke, even though he is young, is like that. It is very satisfying to see him so strongly part of the club on and off the pitch."

"It’s like Lloyd Doyley for his long service. They are two players - one is young and the other is experienced - but they both represent something that all the players should have, they live their lives for Watford."

O’Nien accepts he will have to be patient when it comes to making his debut due to the quality in Watford’s squad.

Speaking in October, he said: "I think anyone in my position wants to be playing first team football and I will be ready whenever I am called upon.

"Whether it is next week, two weeks or next year, I will just stay patient, wait for my opportunity and try to contribute in the best way I can."