Zion Williamson, right, celebrates in a November game with fellow Duke star freshman RJ Barrett. (Grant Halverson/Getty Images)

The NBA has officially proposed lowering its age for draft eligibility from 19 to 18, which would effectively eliminate the so-called “one and done” rule, per a report Thursday. The change to the league’s collective bargaining agreement would have to be signed off upon by its players union, and the NBA is hoping for it to take effect by 2022.

The news was first reported by USA Today’s Jeff Zillgitt, who cited a person with knowledge of the proposal sent by the league to the National Basketball Players Association in reporting that the union and its executive director, Michele Roberts, will review it Monday. The NBA aims to have the age lowered to 18 three years from now, the report said, to give teams sufficient time to prepare for the change.

Zillgitt added that the timing of the proposal is not related to the injury suffered Wednesday by Duke’s Zion Williamson, the star freshman who is expected to be the No. 1 pick in June’s draft. Williamson was reported Thursday to be coping with a Grade 1 right knee sprain, leaving him day-to-day and meaning that he avoided a much more severe injury that could have impacted his draft status and future earnings.

Williamson’s injury was the result of a mishap during a much-anticipated, nationally televised game against Duke’s archrival, North Carolina, that pitted the No. 1- and No. 8-ranked teams in the country. The sight of a player who has become a superstar athlete but must wait several more months before he can begin to fully monetize his status clutching his knee before limping off the court immediately renewed a conversation about the fairness of preventing top high school players from jumping straight to the NBA.

The “one and done” rule, which went into effect in 2006 and mandates that draft-eligible players be at least 19 years old and one year removed from the graduation of their high school classes, was recommended for elimination in April 2018 by an independent body commissioned by the NCAA. Yet only the NBA, not college basketball’s governing body, can change the rule, and the league said at the time that it and the union would “continue to assess [draft-eligibility rules] in order to promote the best interests of players and the game.”

“My personal view is that we’re ready to make that change,” NBA Commissioner Adam Silver said in July, after his league and its union held their respective annual meetings in Las Vegas. He added that the commission’s recommendation, as well as the “college community” sending him the message that it no longer wants one-and-done players, “sort of tips the scale in my mind that we should be taking a serious look at lowering our age to 18.”

In October, ESPN’s Adrian Wojnarowski reported that the league and the NBPA were “struggling” to come to an agreement on lowering the draft-eligible age to 18, with the NBA’s desire for medical information on all draft prospects among the sticking points. It is unclear if the various points of contention have subsequently been worked out.

October also saw the NBA open another, more immediate pathway for elite high school players in the form of “select contracts” that will be available for the 2019-20 season of the G League. Those contracts will allow a few top-level 18-year-old basketball players to sign pacts worth $125,000 for a five-month stint in the NBA’s developmental league.

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