Torreira moved to Arsenal in 2018, signing from Sampdoria in a deal worth £26 million (€30m/$34m).
However, the signing of Thomas Partey from Atletico Madrid paved the way for Torreira to head the other way, with the Uruguayan set to spend at least one season with the Spanish side.
Atleti has long been a landing spot for some of Uruguay's best, with Diego Godin, Diego Forlan, Jose Gimenez and Luis Suarez all representing the club. Torreira is the latest in that list, and he says playing for the club is a dream come true.
“I know that I am a year on loan,” Torreira told Ovacion Digital. “I've been there for four or five days and it seems like it's a lot, because I've been treated very well.
“It is a new opportunity in my life, in which I have fought a lot, because Atlético has always been one of my dreams, one of my goals as a team, and being able to achieve it at the age of 24 is something very important.
“It all depends on how I go during the season, which I hope is very good, and maybe in the future I can stay in the club.”
The midfielder made his Atleti debut against Celta Vigo, starting in what ended up as a 2-0 win for his new side.
Torreira went on to admit that he was not pleased with his last season at Arsenal, which saw him make 39 appearances in all competitions. He attributed part of those struggles to personal problems, but he is hoping his move to Atletico Madrid can help him refocus and rediscover his best.
“This last season at Arsenal, on a personal level, has not been good for me at all,” he added. “I have suffered a lot of things, I have had a lot of personal problems and more than anything my family also suffered.
“With this adventure [at Atletico] everyone is very happy. The most important thing is to be able to enjoy on the pitch, to be able to help teammates and make the fans happy, because in the end, football is just that.”