Former Middlesbrough midfielder Fabio Rochemback has agreed a three-year contract with Sporting Lisbon.
He said: "It is good for both sides.
"Life here (in Portugal) is different to that in England."
Rochemback claimed the chance to work with coach Paulo Bento was also an attraction.
He added: "He is a coach who knows me and played along me. It will be good work with him.
"I hope to help the club and bring some experience and calmness after three seasons in England.
"It is good to be back. I feel at home."