Marc J. Spears of ESPN's The Undefeated, citing a league announcement, was the first to report Mayo's dismissal. Adrian Wojnarowski of The Vertical added that the veteran is eligible to apply for reinstatement in two years.
Spears tweeted the NBA's official statement regarding Mayo's disqualification from the league:
ESPN.com's Brian Windhorst provided some background on Mayo's previous involvement with the NBA's anti-drug policy:
According to Ken Berger of CBS Sports, Mayo's ban is the result of his testing positive for a "drug of abuse" rather than performance-enhancing drugs.
Bleacher Report's Sean Highkin posted the NBA's list of "drugs of abuse" on Twitter:
Mayo appeared in 41 games for the Milwaukee Bucks last season, averaging 7.8 points, 2.9 assists and 2.6 rebounds per contest.
He is an eighth-year pro who had previous stints with the Memphis Grizzlies and the Dallas Mavericks.
The 2008 No. 3 overall draft pick out of USC averaged a career-high 18.5 points per game as a rookie with the Grizz, and his production has been up and down ever since.
Mayo has shuttled in and out of the starting lineup during his time in the NBA, and he boasts career averages of 13.8 points, 3.1 rebounds and 2.9 assists per game.
Should Mayo opt to return to the NBA, he will be 30 years of age when eligible to make his pitch to the league.
Although the West Virginia native never reached his potential as a high lottery pick, he could have been an offensive spark off the bench for a team in 2016-17. His banishment takes away what could have been a bargain option in free agency.
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