Memphis G Calathes suspended 20 games

New York, NY ( - Less than 24 hours before the seventh- seeded Grizzlies open their playoff series against the Oklahoma City Thunder, the NBA announced they will be without the services of reserve point guard Nick Calathes.

The 25-year-old rookie out of Florida has been suspended 20 games for violating the terms of the NBA/NBPA Anti-Drug Program. The suspension kicks in immediately and will carry into the 2014-15 season, depending on how far Memphis goes in the playoffs.

Calathes tested positive for Tamoxifen, a substance that has been banned by the league. The drug is typically used to reduce the side effects of steroid use and help with the production of testosterone.

The loss is a big blow to Memphis, as Calathes established himself as the primary backup to Mike Conley. He averaged 4.9 points and 2.9 assists in 71 games.

Calathes was drafted by Minnesota in 2009 but never played for the Timberwolves, instead opting to spend three seasons in Greece and one in Russia -- winning the Eurocup MVP in 2013 -- before joining the Grizzlies.

Beno Udrih, who was acquired in a midseason deal from New York, will likely be tasked with running the Grizzlies' second unit.