New York Knicks guard J.R. Smith will be suspended five games for testing positive for marijuana, according to Yahoo! Sports' NBA sources.  The NBA is expected on Friday to announce the suspension.

This isn't the first time Smith, the reigning Sixth Man of the Year, has been disciplined by the NBA.  Smith spent 90 days in jail for causing a crash in 2007 that killed a passenger in his car, for which the NBA handed him a seven-game suspension in 2009.  Smith was also suspended 10 games for his role in the 2006 Denver Nuggets-New York Knicks fight, three games for a 2007 nightclub incident and one game in the 2013 playoffs for elbowing Boston's Jason Terry in the face.

Smith signed a three-year, $18 million contract extension in July after averaging 18.1 points per game last season for the Knicks.  The 27-year-old became the Knicks' second scoring option behind Carmelo Anthony, although Smith struggled with a knee issue in the postseason that appeared to affect his shooting - he shot just 29 percent from the field during the Knicks' eventual six-game loss to the Indiana Pacers in the Eastern Conference semifinals.

Smith is critical to the Knicks' success this season.  While Anthony is the team's primary scorer, the Knicks rely on Smith to put up points.  When Smith struggled in the Eastern Conference semifinals, the whole team struggled.

Smith underwent surgery in July to repair a torn lateral meniscus and his damaged patella tendon in his left knee, according to SB Nation.  His recovery is expected to take 12-16 weeks, which would've put his status for the start of the season in question.