It's not always a flawless indicator, but recruiting rankings can be used as a predictive metric for how the NBA Draft might take shape the following year.

For instance, five of the top-10 recruits in the Class of 2018 went on to be selected in the first round of the 2019 NBA Draft. In the 2018 draft, seven of the top-10 recruits in the 2017 recruiting class the preceding year were taken as first-round picks. And in perhaps the best and most recent evidence skewing heavily in the pro-recruiting rankings camp, all 10 of the top 10 recruits in the recruiting Class of 2016 went on to become first-round picks. Recruiting rankings matter.

And yet, they are not the end-all-be-all. For every five-star, no-doubt-about-it stud like Anthony Davis or Zion Williamson that comes along, there's a lesser-known prospect without the hype who grows into first-round credentials. They are fewer and farther between, but they often slip through the cracks to break through into the same tier as those who have carried hype with them throughout high school.

In the 2020 draft, there are a number of players who fit that billing, having been unranked, overlooked or undervalued in high school but growing into potential first-rounders. In the order I expect they'll be selected, here are the six criminally underranked recruits who will soon have the last laugh.

1. Obi Toppin, Dayton

Class (Rank): 2017 (NR)

Obi Toppin is a true zero-to-hero story. In high school he wasn't ranked as a prospect and garnered offers only from Illinois, Dayton, Rhode Island and Mississippi State. He eventually signed with the Flyers.

But he didn't immediately take off from there. Toppin didn't qualify academically to play in his first season. But by 2018-19, as a redshirt freshman, he was surprisingly effective, and his athleticism piqued the interest of NBA suitors. Then by 2019-20, well, the rest is history. 

He became the consensus Player of the Year in college basketball last season and looks like a potential top-five pick in this year's draft. 

Toppin's appeal centers around his high-flying ways. At 6-foot-9, he glides through the air defying gravity, making an impact above the rim as a lob finisher and shot-swatter. But his upside and NBA potential really hinges on his outside shot that so perfectly complements his game. Having shot 41.7% from 3-point range on 103 attempts in two seasons, he looks like a plug-and-play big man who can stretch the floor and finish lobs in the NBA.

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2. Tyrese Haliburton, Iowa State

Class (Rank): 2018 (172)

Fifteen different programs offered Tyrese Haliburton a scholarship as a Class of 2018 recruit, but that still doesn't mesh with just how good he really is. He's a surefire first-rounder, and some scouts view him as a top-five player in this class because of how efficient he was in college, how dynamic he's been in different roles, and the level of his skill and feel.

"Whatever team gets him, they're going to love what he brings as far as IQ and skill," one scout told me recently about him. "He provides a level of understanding for what he would have to be for a team -- a pass-first guard. He's a guy who doesn't carry much risk."

Haliburton's shot mechanics are wonky, but they work. He's skinny, but he compensates with his smarts. He's not overly athletic, but he overcomes it with skill. There are perhaps players in this class with a higher ceiling, but Haliburton, once he adds strength, looks like he'll be one of the safest players in this draft class because of his obvious fit as a ball-handler and 3-point shooter at the NBA level.

3. Devin Vassell, Florida State

Class (Rank): 2018 (200)

It's hard to include Devin Vassell in this category -- he was a three-star, top-200 recruit in the 2018 recruiting class -- but I'd be remiss to gloss over him. Because despite his clear and obvious potential with his long wingspan and 6-5 frame, here's the entire list of programs who offered him a scholarship coming out of high school:

  • Florida State
  • Furman
  • Indiana State
  • North Florida 
  • Stetson
  • Texas Tech

Yes -- that's it. Two power-conference offers for a Georgia recruit who was ranked among the top-10 prospects in the state. (That sound you hear is Georgia and Georgia Tech kicking themselves in the shins for passing on pursuing him.)

Vassell, however, wasn't an immediate star in college. He played sparingly as a freshman, averaging 4.5 points and 1.5 boards per game. But it didn't take him long to figure things out. Last season he was a stellar sophomore, and on an FSU team flush with NBA talent, he stood above the rest. 

Now standing at 6-6 with a wingspan close to 7-feet, a 3-point shot that's fallen at a 41.7% rate in two seasons on 168 attempts, and a defensive mentality that's NBA ready right now, he looks like one of the most safe 3-and-D wings in this draft. Most people I talk to don't expect he'll be available by the time the lottery portion of the draft is complete. 

4. Grant Riller, College of Charleston

Class (Rank): 2015 (NR)

If there was a metric that measured college accomplishment and production with the level of hype a player received, Grant Riller's scale would be all sorts of out of wack. He averaged 18.7 points per game in four seasons at the College of Charleston, twice earning All-CAA honors. And yet some may not even know about him because he played in a small conference and he wasn't highly-ranked coming out of high school.

In fact, he wasn't ranked at all -- and Charleston was his only offer coming out of high school.

And yet, Riller might be a first-round pick in this year's draft. He's an incredible shot-maker who can score it from all three levels with confidence. And more than that, he's aggressive with the ball in his hands. When he's running the show, he loves playing downhill and applying pressure on defenses by challenging the rim, or stopping on a dime and pulling up from 25 feet. His touch from anywhere on the court is excellent.

He's not particularly flashy with his physical profile or his athleticism, but Riller might be one of the best values in this draft -- someone I'm confident will have a role in the NBA because of his experience and scoring ability.

5. Paul Reed, DePaul

Class (Rank): 2017 (271)

There weren't many Paul Reed believers when he came out of high school in 2017. Only four programs offered him a scholarship: DePaul, Kansas State, Murray State and Rutgers. As a recruit, he was ranked as a three-star prospect ... and barely top-300 in his class.

Reed, however, has grown from fringe top-300 in his recruiting class into a potential top-30 (!) player in this draft class. He's grown (literally) four inches to 6-9, and at DePaul, he developed into one of the best all-around defensive players in the sport. He's a selfless team player who loves crashing the boards and affecting the game on defense, and he can defend multiple positions because of his size and quickness.

For his career, he's a 33% 3-point shooter. So there's some concern that he may be a one-dimensional forward who can't contribute much offensively. But he was criminally miscast on DePaul as a go-to option last season that dragged his numbers down. As a role-playing defender, I can see him being league-average as a 3-point shooter -- and hitting at a rate closer to the year prior, when he made 40.5% of his 3-pointers. 

Regardless, his effort and impact defensively should outweigh whatever inefficiency he may bring offensively. 

6. Desmond Bane, TCU

Class (Rank): 2016 (NR)

Credit the TCU staff for this gem-of-a-find. They were the only program to offer Desmond Bane a scholarship. And that was an offer made at the time to a little-known Indiana native who had no recruiting ranking.

Bane made their bet worthwhile ten times over. He became a two-time All-Big 12 performer and groomed himself into a reliable marksman from 3-point range, who enters the draft as one of, if not the, best outside shooters in this draft.