Portland Trail Blazers guard Elliot Williams underwent successful surgery today to repair left patella instability.

Dr. Neal ElAttrache performed the surgery at the Kerlan-Jobe Orthopaedic Clinic in Los Angeles with assistance from Portland team physician Dr. Don Roberts.

The first-year player will miss the remainder of the 2010-11 season after previously undergoing a similar procedure on his right patella on Nov. 12, 2010.

Portland selected Williams with the 22nd overall pick in the first round of the 2010 NBA Draft. He has not appeared in a game for the Trail Blazers this season.

Williams, 21, posted averages of 17.9 points (45.9% FG, 36.6% 3-PT, 75.8% FT), 4.0 rebounds, 3.8 assists and 1.32 steals in 34 games (all starts) as a sophomore at Memphis in 2009-10, earning All-Conference USA First Team and Conference USA Newcomer of the Year honors.

The 6-5, 183-pound guard played his freshman year at Duke in 2008-09, where he averaged 4.2 points, 2.3 rebounds and 0.7 assists in 34 games before transferring to Memphis.