Perennial Premier League strugglers Sunderland moved to head off a goalkeeping crisis Wednesday by snapping up Portuguese stopper Michael Simoes Domingues from Boavista on a two-year deal.

The 25-year-old becomes David Moyes's 10th signing since arriving as manager in the summer and comes outside the transfer window after what Sunderland called "a technical issue" meant the deal could not be done by the deadline on August 31.

"However FIFA are satisfied that both teams fulfilled their commitments and the transfer has now been approved," the Premier League side said on its website.

"Mika" previously played for Benfica and Atletico CP in Portugal and represented the country at U20 and U21 level.

Moyes was desperate to get in the Portuguese after losing first-choice goalkeeper Vito Mannone for three months after he tore elbow ligaments.