Transfer window: Norwich's Daniel Ayala joins Middlesbrough

Middlesbrough have signed Norwich defender Daniel Ayala for fee thought to be £350,000, after a loan spell.

The Spaniard, 23, has made 12 league starts since in October, double his tally during two-and-a-half years at Carrow Road.

Ayala spent last season but did not play after the

He has agreed a three-and-a-half-year deal, and becomes head coach Aitor Karanka's first permanent signing.

Karanka in November, and since then goalkeeper defender and midfielder have all arrived on loan deals.