Newcastle United's Mikel Merino has joined Real Sociedad.
The club today confirmed the midfielder's departure to the La Liga club.
Sociedad activated a release clause in the contract Merino signed last year following his move from Borussia Dortmund.
Merino posted a message to Newcastle fans on Twitter after the move was announced.
The 22-year-old tweeted: “Thank you very much for this amazing year to all the toon family. Massive experience that I’ll never forget.
“Thanks to the outstanding fans, who made me feel at home. All the best for the future and Howay the lads!”
Thank you very much for this amazing year to all the toon family. Massive experience that I’ll never forget.Mikel Merino
United signed free agent Ki Sung-yueng last month as a replacement for Merino.
A club statement read: "Mikel Merino has completed a permanent move to La Liga side Real Sociedad.
"The 22-year-old leaves St. James’s Park for an undisclosed fee, having made 24 Premier League appearances for the Magpies, scoring once in a 1-0 victory over Crystal Palace
"Merino initially joined Newcastle United on loan from Borussia Dortmund last summer before the option of a permanent transfer was exercised in October 2017.
"The midfielder’s new club, which is based in San Sebastian – just over 50 miles from his hometown of Pamplona – finished 12th in the Spanish top flight last season.
"Everyone at Newcastle United wishes Mikel the best for the future."
Merino had become frustrated with a lack of first-team starts in the second half of last season.
"It was a pity, because obviously he wanted to play more football," said Benitez.
"He’s a young player, and he struggled to get back into the team, because (Mohamed) Diame and (Jonjo) Shelvey were doing so well."