Spanish champions Barcelona's new signing Brazilian international star Neymar was paraded in front of 50,000 patient fans at the Camp Nou on Monday.
"I am very happy and excited to be a Barca player, it is a dream come true," said the 21-year-old.
However, he insisted World Player of the Year Lionel Messi will continue to be the key player in the Barca side.
"I am at something that is more than a club. I came here to help the team and Messi will continue being the best in the world."
Neymar arrived in the Catalan capital just after 1300 local time (1100 GMT) and after a brief photo opportunity at the stadium underwent a two-part medical, firstly at a local hospital and then at the club's training ground.
He was then transported back to the stadium where he officially signed the already agreed five-year deal that will keep him tied to the club until 2018.
According to Spanish media, the transfer was valued at between $51.7 million and $64.6 million.
Finally he came on to the pitch to entertain the huge crowd that had been awaiting his arrival by performing a series of ball skills as he donned the Barca shirt for the first time with Neymar Jr on the back, although he has not as yet been designated a squad number.