The Thunder signed Reggie Williams on Monday, the team announced.
The 30-year old played his first two NBA seasons with the Warriors.
Over 24 games (10 starts) in 2009-10, he averaged 15.2 points, 4.6 rebounds and 2.8 assists per contest.
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Across 80 games (nine starts) in 2010-11, he averaged 9.2 points and 2.7 rebounds.
Williams played the next two campaigns with Charlotte, appeared in three games with Oklahoma City in 2013-14, and saw action in 20 games with the Spurs in 2014-15.
He played in Russia last year.