Middlesbrough completed its first January transfer signing on Thursday when South Korea striker Lee Dong-Gook was awarded a work permit.
Lee signed an 18-month contract after arriving on a free transfer from Pohang Steelers. Terms of the 27-year-old striker's contract were not disclosed.
Lee returned to South Korea to obtain his visa and is expected to join Middlesbrough next week.
Lee missed last summer's World Cup in Germany due to a cruciate ligament injury. He has scored 22 goals in 64 appearances for the national side.
Also on Thursday, Middlesbrough released defender Ugo Ehiogu and midfielder Ray Parlour.
Ehiogu signed with Rangers on Monday. The 34-year-old Ehiogu was once the club's record signing at 8 million pounds (US$15.7 million; euro12.1 million).
Parlour will train with Arsenal, for whom he made 468 appearances between 1991 and 2004. Parlour will work to regain match fitness but will not be offered a contract.