The Croatia international was officially unveiled as a Barca player on Tuesday after completing his reported €20 million move from Liga rivals Sevilla and penning a five-year contract in Catalunya.
Cesc Fabregas previously wore the same jersey before being sold to Chelsea earlier this summer, and Rakitic, 26, admitted he is delighted to follow in a long line of illustrious midfielders.
“it's special to wear the same number as Pep Guardiola,” Rakitic told a press conference.
“It's an honour to wear the No.4 shirt, he made history as player and coach. I hope to be as successful as him.”
The former Basel and Schalke man, who captained Sevilla to Europa League glory last term, admitted he is yet to speak in-depth to Barca boss Luis Enrique, but said he is well aware of the quality of his new team-mates.
"I spoke to Luis Enrique but not much because I was focused on the World Cup. It wasn’t not easy to train with peers and all wondering if it was already closed,” he continued.
"I want to win more trophies. I'm really motivated and I want to get better as a player.
"I hardly need to mention Lionel Messi and Neymar. I've seen them up close. A bad pass to them can even turn out to be a great pass given their quality.
"Hopefully I will try to make them a little better and they will do the same for me."
Barcelona announced that Sevilla have asked for the financial details of the transfer not to be released to the public.