The 19-year-old already has five caps for the Japanese national team and is widely regarded as one of the top talents in that country after representing them at every level from U16 through to U23.

He spent last season on loan with J1 League outfit Fagiano Okayama, making 28 appearances and scoring six goals and catching the attention of several top European clubs.

Speaking at his unveiling, Sato said Valencia has a strong reputation among Japanese football fans and was a club he was always interested in joining.

"Before coming here I already knew how big Valencia CF were in Spain. Every day I'm noticing it more and I'm very happy to be here," he said.

"All the Japanese players know Valencia CF and rate the club highly. When they found out I was coming here, they were surprised and congratulated me a lot.

"Coming to Valencia CF was what I was wishing for, and I didn't hesitate to choose the club. It's my personal challenge to grow here.

"I've gradually started training with the team. I've already kicked the ball around, the feeling is very good and my teammates are treating me very well. I'm very happy.

"The training sessions are very technical and fast-paced, I'm really enjoying them. I really like playing with the ball at my feet, and there are a lot of very good players here. If I had to name one in particular, it would be Guido."

In terms of his preferred position, Sato is equally adept at playing on the wing or as an attacking midfielder behind a striker and has drawn plenty of comparisons to Japan legend Shinji Kagawa.

"When I debuted I played as a number 8, and then I started playing in the hole. I did that last year and did a good job. I'm good both as a no.10 and as a winger," he said.

"[Kagawa] was my idol since I was little. I spoke with him and he congratulated me when I told him I was coming to Valencia CF.

"I believe LaLiga is the best league in the world, both in terms of the level of football and the fans. As for Valencia CF's style of play, they are very fast, they work very hard, and I want to contribute to that.

"It's an honour to be the first Japanese player in Valencia CF's first team squad. I have to work hard and I want to play well and help the team.

"They say LaLiga is difficult for Japanese players, but that doesn't matter, the important thing is to work hard and give your best. Take Kubo is producing good results and is an example to follow."

Valencia sign Japanese star Ryunosuke Sato