Sebastian Coates has left Sunderland after the defender's loan deal at Sporting Lisbon was made permanent.
The 26-year-old joined the Portuguese side in January 2016 and has made 38 appearances for the club.
The Uruguay international arrived at Sunderland on a loan deal from Liverpool in 2014 before becoming Dick Advocaat's first signing as head coach the following year.
Coates made 32 appearances for the Black Cats during his time on Wearside.
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