Duke’s Zion Williamson grimaces after getting injured against North Carolina. (Rob Kinnan/USA Today)

We’re still waiting for word on the exact severity of Zion Williamson’s knee injury, but at least one NBA player, Isaiah Thomas, wasn’t wasting any time Wednesday advising the Duke star to stay out of action until he turns pro. A number of other NBA players, including LeBron James, also offered reactions to Williamson’s plight that ranged from well wishes to jabs at the NCAA for not better compensating its top athletes.

“Zion sit yo a-- down,” Thomas tweeted, “and we will be ready for you in the big boy league.” Williamson has been the front-runner to go No. 1 in June’s NBA draft, with some considering him the most exciting prospect since James himself.

The top-ranked Blue Devils’ freshman sensation went down in the first minute of a much-hyped showdown Wednesday against No. 8 North Carolina. James was among the many who immediately were struck by the way Williamson’s Nike shoe fell apart on the play.

After the game, an 88-72 Tar Heels win, Duke Coach Mike Krzyzewski told reporters that Williamson had suffered “a mild knee sprain.” He said the knee was “stable” but added of his young star, “We don’t know how long he’ll be out.”

To Atlanta Hawks rookie Trae Young, Williamson’s injury should effectively signal the end of his college career, given the near-certainty that he’ll declare for the draft. “Zion need to chill out the rest of the season,” Young tweeted.

Thomas took issue with the NBA’s rule mandating that players must be at least 19 and one year removed from their high school class’s graduating year to be eligible for the draft. Given the enormous promise he showed and attention he received while still in high school, Williamson may well have jumped straight to the pros if he could have, rather than spending a season at Duke.

“Let these kids go straight out of [high school]!!!” Thomas exclaimed on Twitter. “Too much on the line to be messing with college if you got a legit chance to turn pro.”

“One injury can change somebody career,” added Thomas, a Denver Nuggets player who suffered a hip injury while with the Boston Celtics that derailed the likelihood of him earning a nine-figure contract. In a hashtag, he said he was “looking out for the players.”

Referring to a Duke-UNC matchup that had tickets selling for thousands of dollars on the secondary market, the Utah Jazz’s Donovan Mitchell tagged the NCAA in tweeting, “Again let’s remember all the money that went into this game … and these players get none of it … and now Zion gets hurt … something has to change.”

Thomas’s comments echoed those made over a month ago by former NBA great Scottie Pippen, who claimed that if he were Williamson, he would “shut it down.” The ex-Chicago Bulls player, who is now an analyst for ESPN, said on that network’s “The Jump” that he “would stop playing,” because Williamson “could risk a major injury that could really hurt his career.”

If Krzyzewski is correct and Williamson has indeed dodged a severe knee injury, the 285-pound athletic marvel might still opt to play it safe and sit out the rest of the season, even at the possible cost of missing a shot at a national championship. Meanwhile, a former Tar Heel, the Dallas Mavericks’ Justin Jackson, and a former No. 1 pick, the Orlando Magic’s Markelle Fultz, were sending some prayers Williamson’s way.

The Celtics’ Terry Rozier initially reacted to the incident Wednesday by encouraging Williamson to eventually sign with the shoe company he endorses, Puma, as opposed to Nike. Rozier subsequently tweeted that he was unaware Williamson got injured on the play.

“We are obviously concerned and want to wish Zion a speedy recovery,” a Nike spokesman told The Washington Post in a statement via email. “The quality and performance of our products are of utmost importance. While this is an isolated occurrence, we are working to identify the issue.”

Also wishing Williamson a speedy recovery was former NBA all-star Carlos Boozer. Unfortunately, the Duke star likely never got the kind thoughts, as Boozer mistakenly put in his message the Twitter handle for Utah’s Zion National Park.

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