Wolves have completed the permanent signing of on-loan Jonny Castro Otto from Atletico Madrid.
Full-back Otto joined Wolves on loan during the summer and has made 22 appearances in all competitions.
The 24-year-old Spaniard has become the club's first signing of the January transfer window for a fee of £15m and has signed a deal until 2023.
Otto immediately moved on loan to Celta Vigo when he joined Atletico in 2018 and never played for the Madrid club.
"I'm really happy to continue to be involved with the team," he said. "I am very happy here, the truth is that it was very easy to decide.
"They are treating me very well, there are great staff, great team-mates and great supporters."
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