La Liga - Da Silva joins Real Zaragoza
The Paraguay international, an integral part of their World Cup campaign in South Africa last summer, moved to the Stadium of Light from Mexican club Toluca in the summer of 2009 and made 20 appearances during his first season on Wearside.
But the 30-year-old has found opportunities harder to come by this term, enjoying just three first-team outings, and will now switch to the Primera Division with 15th-placed Zaragoza.
A statement on the Sunderland website said: "Paraguayan defender Paulo Da Silva has joined Spanish side Real Zaragoza.
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