The NBA is suspending New York Knicks center Joakim Noah 20 games for violating its anti-drug program, league sources told The Vertical.

The NBA announced the suspension on Saturday.

Noah tested positive for an over-the-counter supplement that is prohibited under the outgoing Collective Bargaining Agreement, league sources said.

Noah, 32, is expected to serve 10 games of the suspension to finish out the 2016-17 regular season and 10 games to start the 2017-18 season, league sources said.

The National Basketball Players Association’s investigation concluded that Noah hadn’t “knowingly or willingly” violated the policy and cooperated fully with the league’s probe, league sources said.

Noah underwent arthroscopic surgery on his left knee on Feb. 27, effectively ending his season. He had recently started running and conditioning, league sources said.

After signing a four-year, $72 million free-agent contract to leave the Chicago Bulls for New York, Noah averaged only five points and 8.7 rebounds in 46 games this season.

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