The 26-year-old, who began his career with Espanyol, joins Betis on loan after Leeds United was relegated from the Premier League at the end of last season.
Roca was highly-rated as a youngster and after making 121 appearances for Espanyol, he joined Bayern Munich, where his career stalled and he made just 24 appearances in all competitions in his two years with the German giants.
He moved to Leeds last season and although he was a first-team regular, he was unable to stop them dropping into the Championship, and Leeds has allowed him to move on loan to help ease the burden on their wage bill.
Roca is likely to replace Portuguese midfielder William Carvalho, who looks likely to leave Betis this summer, while there are also doubts about the future of Argentinean international, Guido Rodriguez at the club.
–IANS
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