The 21-year-old came off the bench for the Catalan giants in a 2-2 draw against Lechia Gdansk in Poland.
Neymar, who was signed from Santos for €57 million in May, was substituted on with 11 minutes to play and showed promising signs in his brief cameo as the countdown to the La Liga season continues.
The young forward, who feels he needs more time to get up to speed, enjoyed linking up with star Lionel Messi in the match.
"I have fulfilled a dream," Neymar said afterwards.
"I think I need a little more time to get into shape.
"Messi is a great person. He is an idol for me and I am very happy to be here and that I get the chance to play with him.
"Speaking with Messi is very easy. He's a great player, I'm happy to be here. I am just thinking of helping."
Neymar could make his first Barcelona start against former club Santos at Camp Nou on Friday in the club's next pre-season friendly.
New manager Gerardo Martino – who has replaced Tito Vilanova after he resigned to fight throat cancer – will take charge of his first Barcelona match on Friday.
"It will be a bit strange, different, but now I defend Barca's colours and I'll give it my all," Neymar said of the match.
