Aleix Vidal sealed his move to Barcelona from Sevilla on Monday, signing a five-year contract after undergoing a medical.
Barca revealed on Sunday that an agreement had been reached to bring the versatile right-sided player to Camp Nou on a deal until 2020.
Vidal is unable to make his debut for the European champions until January due to the transfer embargo that the club is under.
The 25-year-old spent just one season with Sevilla after moving from Almeria, but made a big impact as Unai Emery's side won the UEFA Europa League for a second successive season.
Vidal's impressive displays earned him a first call-up to the Spain squad, for their upcoming friendly with Costa Rica and Euro 2016 qualifier against Belarus.
He appeared on the pitch at Camp Nou for the customary presentation before being introduced to the media.
"After the birth of my daughter, this is the most important day of my life. I am back at what used to be my home," Vidal, who played for Barca for one season alongside Jordi Alba in the Under-14 B team, told the media.
"If it's the start of a winning cycle, then so much the better."
The future of Barca coach Luis Enrique has been the subject of much speculation, but Barca new boy Vidal expects the former Spain international to stay at the club.
"From the conversation I had with Luis Enrique I presume he'll be the manager for next season," he said.
Vidal also spoke of his desire to spend the rest of his career with the Catalan giants.
"I've played for a lot of teams before arriving at Barca, but I hope this one's the last," he said.
"I went through a lot to get here and I'm living a dream. I always try to give my best.
"There's no better way to learn than by playing with these team-mates.
"I'm coming here to find my niche. These four months will be good for me to improve in certain areas."
