Pablo Mari says it is a "great achievement" for him to earn a move to Arsenal.
Mikel Arteta's side completed the signing of the defender from Flamengo in an initial loan deal on Wednesday.
Arsenal have paid £4m to borrow the Spaniard until the end of the season, when they will have the opportunity to buy him outright for a further £8m.
And the 26-year-old says he is "delighted" to be back in the Premier League.
"When I spoke to my agent, it was a big thing that Arsenal were interested in me," he told Arsenal Player.
"This is one of the best clubs in the world, so I am absolutely delighted to be joining. I’m really looking forward to playing in this jersey and helping my team.
"The conversations started a couple of weeks ago. Arsenal told us that they were interested. We’d just won everything with Flamengo – I won the league and the Copa Libertadores and was also named best centre-back in America, so that will have helped Arsenal notice me.
"It’s a great achievement for me to come to Arsenal and it all happened in basically two weeks.
"I’m kind of used to [all the attention] from Brazil, where the fans are really passionate about Flamengo. I’m used to a lot of media interest so I know what to expect when joining a big club like this one. It’s a normal thing for me now."
Following Monday's 2-1 victory over Bournemouth in the fourth round of the FA Cup, Arsenal return to Premier League action against Burnley on Sunday.
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