Hamidou Diallo makes strong impression during testing at the NBA draft combine

Hamidou Diallo’s vertical leap was the second best in combine history. (AP)

Hamidou Diallo increased the chances he’ll never play for Kentucky on Thursday afternoon without passing, shooting or dribbling a basketball even once

The Kentucky guard bolstered his stock by posting eye-popping numbers during testing at the NBA draft combine in Chicago.

Diallo’s 44.5-inch max vertical leap was the best mark of the day by three inches and the second highest in combine history. Only former Kansas wing Kenny Gregory’s 45.5-inch leap in 2001 was better, per Jonathan Givony of DraftExpress, though ex-Memphis guard D.J. Stephens did clear a record 46 inches at the Portsmouth Invitational Tournament in 2013.

A jaw-dropping vertical doesn’t guarantee a prospect will hear his name called on draft day as both Gregory and Stephens can attest, but Diallo’s other measurements confirmed his reputation as one of the most physically gifted players in this draft class. He posted the second fastest three-quarters-court sprint of the day and measured 6-foot-5 in shoes with a wingspan of just over 6 feet, 11 inches, longer for example than UCLA power forward T.J. Leaf or BYU power forward Eric Mika.

The buzz from Diallo’s strong combine performance increased the chances that his Kentucky career may be over before it begins.

Diallo enrolled at Kentucky at the start of spring semester and practiced with the Wildcats during the second half of the season. but he chose not to risk jeopardizing his draft stock by appearing in any games. He then declared for the draft without hiring an agent last month, giving himself until May 24 to withdraw and return to school if he chooses.

If Diallo makes the rare preps-to-pros jump, he would be taking advantage of the same loophole that Thon Maker did a year ago. Since Diallo graduated from high school last spring and turns 19 in July, he’s eligible for the draft without playing a year in college first.

Diallo is a potential first-round pick if he stays in this year’s draft because of his physical tools and sky-high upside. His massive wingspan, explosive first step to the rim and high-level motor make it easy to imagine a team in the latter half of the first round falling in love with his long-term potential and opting to try to develop him.

If he returns to Kentucky, there will be no hiding anymore, something that could hamper his stock or boost it depending on how things go.

On one hand, he could improve his ball handling, passing and shooting and solidify himself as a 2018 lottery pick. On the other hand, he could suffer an injury or fail to meet expectations and prove that he’s more athletic marvel than skilled basketball player.

For Kentucky, it’s difficult to overstate the importance of getting Diallo back next season. The Wildcats will likely lose eight of their top nine players from last season, meaning they will lean even more than usual on their newcomers.

Diallo was expected to be a centerpiece of an incoming class that is college basketball’s best. The Wildcats have landed a half dozen five-star recruits and remain in the running for Pittsburgh transfer Cameron Johnson and elite center prospect Mohamed Bamba.

Diallo would not tell reporters in Chicago how high his stock needs to be for him to remain in the draft, but an answer he subsequently gave might be very revealing. Asked if he’d be comfortable being stashed in the D-League next season, Diallo didn’t balk.

“I would just wait for my chance to prove that I belong,” he told SECCountry.com. “I think everybody has a different route to the NBA. Whatever best suits them.”

As long, fast and athletic as Diallo looked on Thursday, it’s likely an NBA team will take a chance on him in the late first or early second round.

Is that enough reason for him to leave Kentucky without ever playing a game? In the next two weeks, he’ll have to make that decision.

– – – – – – –

Jeff Eisenberg is the editor of The Dagger on Yahoo Sports. Have a tip? Email him at daggerblog@yahoo.com or follow him on Twitter!