Portuguese goalkeeper Mika has joined Sunderland on a two-year deal for an undisclosed fee from Boavista, the Premier League club said on Wednesday.
The 25-year-old arrives at the Stadium of Light following approval from FIFA after the Portuguese club were unable to complete their requirements before the Aug. 31 transfer deadline due to technical issues.
Sunderland's first-choice goalkeeper Vito Mannone has been ruled out for around three months due to an elbow injury with Jordan Pickford deputising.
Mika, 25, made 26 appearances for Boavista as they finished 14th in the Portuguese league table last season.
Sunderland host Everton in the Premier League on Monday.
(Reporting by Nivedita Shankar in Bengaluru, editing by Ed Osmond)