Midfielder Xavi will leave Barcelona this summer after 17 years at the Catalan club to join Qatari side Al Sadd in a three-year deal.
The Spain midfielder, 35, has won eight league titles and three Champions League trophies with the club.
He can add two more trophies at the newly crowned La Liga champions, with Barcelona in the Copa del Rey and Champions League finals.
"I couldn't have had a better career," he said. "It was a tough decision."
His final league game will see him lift his eighth La Liga title against Deportivo La Coruna on Saturday.
Barcelona then face Serie A champions Juventus in the Champions League final on 6 June.
"We have a unique opportunity to make history," said Xavi. "I think the Qatar project is nice, and it's ideal for me. In the future I'd like to come back to Barca.
"I had a very good offer to renew with Barca, but I didn't even tell my mother. I want to keep playing. I know I can still perform, although it'll be in a lower-level league.
"Barca will continue to be great without me. I'm convinced."
According to his agent, Ivan Corretja, Xavi would also become an ambassador for the 2022 World Cup to be held in the Gulf state, and look to start his coaching qualifications.
The Spanish player has also represented his country 133 times - a record for an outfield player - and was an integral figure in helping Spain win the 2010 World Cup and the 2008 and 2012 European Championships.