Paris Saint-Germain on Friday completed the signing of 29-year-old Brazilian centre-back Alex from Chelsea on a two-and-a-half-year contract.
"I knew about PSG's immense stature and that made me want to come," Alex told journalists at his presentation.
"I also spent two years with (PSG coach) Carlo Ancelotti at Chelsea. For the past two months I've wanted to leave Chelsea and we finally opened talks with PSG. Everything went very well."
Alex began his career with Santos before leaving Brazil in 2004 and joining Chelsea, who immediately loaned him out to PSV Eindhoven, with whom he won three consecutive Dutch league titles.
He won a Premier League and FA Cup double under Ancelotti at Chelsea in 2010.
The defender has 18 Brazil caps and won the 2007 Copa America.
Alex's arrival means that PSG now have six senior centre-backs on their books and he will compete with Diego Lugano, Zoumana Camara, Milan Bisevac and Sylvain Armand for the right to partner club captain Mamadou Sakho.
"It's a good opportunity, at the price, but also because of his desire to come," said Ancelotti.
"I know him very well. He's a fantastic man and a fantastic player. He's a good investment for the team.
"He's played in England, the Netherlands, in the national team and many times in the Champions League. Physically he's strong and he's a good professional. I like this kind of player."
Meanwhile, Ancelotti said that Manchester City striker Carlos Tevez could join PSG at a later date after talks over a move in January broke down.
"For Tevez, it's finished," said the Italian.
"For the future, I can't say. There might be another opportunity. In the future, we'll have to buy another striker.
"We spoke to him and he told us that he'd be happy to play for PSG. But when you can't find an agreement...
"In the end, the club decided that it wasn't the right opportunity. It's nothing to do with behaviour. There's the supply and the demand, and if they don't match up, it's over."
Ancelotti also refused to discuss PSG's reported interest in Inter Milan's Brazil-born Italian holding midfielder Thiago Motta.
"He's a good player, but I don't want to talk about the transfer window," he said.