CHICAGO - Dante Exum is a mystery.

There are videos of him galloping toward the rim and finishing with thunderous dunks, displaying his off-the-charts athleticism. But outside of those YouTube clips, the 6-foot-6 point guard from Australia is an unknown in the United States. And it was set up that way.

The 18-year-old has been held out of a competitive team setting since leading Lake Ginninderra Secondary College to the Australian National High School Basketball Championships title in January. It has been even longer since he competed in an international setting - July's FIBA under-19 World Championships.

As a result, Exum, who has links to the 76ers, is probably the biggest question heading into the NBA draft next month.

"I guess they all have an idea what I'm about," Exum said Thursday of NBA teams while in Chicago for the draft combine. "They've seen some of the college players play 40-game seasons, and they haven't seen me a lot. So I guess when they are trying to look at tape, they can't see a lot of tape of me."

While those tapes are impressive, several scouts wonder if he'll be able to make a successful leap to the NBA.

Dominating Australian high-schoolers and 19-year-olds at a world championship doesn't compare to what other top draft prospects - Andrew Wiggins (formerly of Kansas), Jabari Parker (Duke), Joel Embiid (Kansas), and Julius Randle (Kentucky) - did last season as college freshmen.

But at the same time, Exum hasn't been scrutinized the way those four players have.

"They have their advantages and disadvantages, because [scouts] haven't seen me since last year, July," he said. "It works both ways."

The Sixers arguably know more than any other team about Exum because of his relationship with coach Brett Brown.

Brown coached the Australian national team. Three years ago, he invited Exum, then 15, to the Boomers' training camp. And when Brown was an assistant with the Melbourne Tigers, he coached Cecil Exum, Dante's father.

Exum is regarded as a player with a huge upside, but one who could also be a major bust.

He moved to Los Angeles in February to participate in two-a-day workouts in preparation for the draft. There have been reports that Exum has struggled during those drills. One NBA front-office executive said he doesn't believe Exum is capable of playing point guard in the NBA.

But the executive, who requested anonymity, added that Exum's height and athleticism are hard to overlook because of Michael Carter-Williams' success this season.

Like the Sixers rookie (6-6, 185 pounds), the 196-pound Exum towers over many other point guards. But like Carter-Williams, Exum's perimeter shooting is a huge shortcoming.

The executive pointed out, however, that Carter-Williams was the rookie of the year. That, the executive said, will entice teams to draft Exum. He said he just doesn't believe Exum will play point guard.

Apparently, he's not alone in the evaluation. Exum was grouped with the shooting guards at the combine.

But . . .

"I see myself as a point guard," Exum said. "I've always been in the point-guard position. That's where I feel more comfortable. I think that's where I'm inching myself into the draft as. That's where I see myself playing."

He sees similarities to Manu Ginobili and Russell Westbrook because of their ability to drive to the basket. Exum also said he's a good defender with great foot speed.

"And that's something we definitely have been working on the last two months," he said. "If I want to be a point guard, I'm going to be in the league with a lot of fast point guards. So I think working on my foot speed is definitely going to be something I need to keep working on."

But he's doing all this behind closed doors. As a result, his YouTube clips from the summer are the only thing fans can go on.

But if they listen to Exum, they might as well stop watching.

"My game has changed a whole lot since those clips," said Exum, who added that he is determined to be a vocal leader. He said his game is based on beating his defender off the dribble and finding open players. "And I think that puts me in a good position to be a good point guard."

We will find out for ourselves next season.

Inside the Sixers: Pompey's Top 10

Inquirer 76ers beat writer Keith Pompey ranks the top 10 prospects in this year's NBA draft.

1. Andrew Wiggins SG/SF, Kansas

The Canadian is hands-down the best athlete in the draft. Wiggins has the potential to develop into one of the league's elite players.

2. Jabari Parker SF, Duke

The Duke product is arguably the most NBA-ready player in the draft and appears to be a safe pick.

3. Joel Embiid C, Kansas

If not for his back injury, Embiid would be at the top of the draft class. He has a good mid-range game and is an exceptional shot-blocker and rebounder.

4. Julius Randle PF, Kentucky

He finishes well around the rim and has a solid face-up game. Randle is also effective in pick-and-rolls and pick-and-pops.

5. Dante Exum PG, Australia

Like Wiggins, Exum has a huge upside. At 6-foot-6, he is a long point guard who has a knack for getting to the rim.

6. Aaron Gordon PF, Arizona

Though a bit undersize (6-71/2 without his shoes), he's an athletic freak. Gordon is explosive going to the basket, has a 41-inch vertical leap, and is an excellent defender.

7. Marcus Smart PG, Oklahoma State

He is one of the most competitive players in the draft and excels at penetrating and finishing. Smart adds a lot of value because he is able to play point guard and shooting guard.

8. Noah Vonleh PF, Indiana

He just might become the steal of the draft. He's a beast on the block and has a solid perimeter game.

9. Doug McDermott PF/SF, Creighton

While his stock is dropping, McDermott's elite three-point shooting cannot be overlooked. The son of a coach, he also has a high basketball IQ.

10. Gary Harris SG, Michigan State

Like Gordon, Harris is a bit undersize (6-21/2 without his shoes) at his position. He makes up for that, however, with his strength and physicality. Harris has a knack for attacking the rim.