Sources told ESPN.com that Oberto -- who has turned down several offers from Europe in recent weeks because he was determined to keep playing in the NBA -- is joining the Blazers on a one-year deal to fortify their depth as Greg Oden and Joel Przybilla continue to recover from the serious knee injuries they suffered last season.
Oberto, 35, played for Washington last season after spending four seasons in San Antonio alongside countryman Manu Ginobili.
On the eve of the 2009 draft, San Antonio dealt Oberto to Detroit as part of a three-team deal that landed Richard Jefferson with the Spurs. Oberto was immediately released by the Pistons, enabling him to sign with the Wizards.
The Blazers, who count Marcus Camby as their only healthy true center, have been looking for a veteran big man with Oden and Przybilla still healing.
But adding Oberto will require the Blazers to release two players before opening night rosters are finalized Monday because they're already carrying 16 players, one over the league limit.
Marc Stein is a senior NBA writer for ESPN.com.