Dennis Smith, Jr. was one of this summer’s standout players. At Summer League, the Dallas Mavericks’ first round draft pick elicited “oohs” and “ahhs” from the crowds during pregame warm-ups. It’s here where he showed off the ease of his athleticism and dunking prowess. In games, he also impressed. His missed dunk attempt against the Sacramento Kings last Thursday, which brought the Thomas & Mack Center to its feet in a collective gasp, quickly went viral. Seeing this, it’s easy to forget that he’s more than just a human highlight reel.

In Las Vegas, Smith, Jr. played with a degree of discipline on the court that’s rare for most rookies. That’s one of the reasons he became a standout at the summer tournament. But it’s his willingness to listen to his coaches and teammates that cemented him as a leader on the team.

While Smith, Jr. made it look easy offensively, it was a team effort that helped him understand the defenses teams were throwing at him. He took what was available and controlled the pace of the game.

“He’s adjusted,” Mavs’ Summer League head coach Jamahl Mosley said. “His teammates have done a great job talking to him, telling him how to change positions, where he’s coming from, and how they’ll set the screen. It’s kind of been a group effort in how he’s adjusted to it so I think he’s done a very good job.”

That much is apparent. Smith, Jr. averaged 17.3 points on 45.7 percent shooting, 4.8 rebounds, 4.2 assists, and 2.2 steals in his six games. Most were team-highs. But not everything came as easy as buckets for the rookie. He is still learning to play with poise and not letting his emotions get the best of him on the court.

“I’m taking it step by step,” Smith, Jr. said. “I’m a guy that wears my heart on my sleeve. That’s just the way I was born and I carry that my whole life. I’m getting better with it. It’s just going to take some time.”

Unfortunately, Smith, Jr.’s body language wasn’t always his friend. He appeared frustrated with his teammates at times, especially if they missed an open look after he fed them the ball. To correct this, his coach thinks it’s a matter of finding himself.

“I really just think he needs to find his identity,” Mosley said. “At the end of the day, there’s going to be a ton of things that we ask him to work on. But body language, demeanor, how he approaches each game, having a game plan each time he walks on the floor is going to go a long way whether he’s with veterans or young guys. Him controlling who he is is going to be huge.”

25 pts, 7-15 FG, 4-8 3ptFG, 7 reb, 2 ast, 3 stls

And one explosive near dunk you have to see.

— Mike Leslie (@MikeLeslieWFAA) July 14, 2017

That’s just one of the things Smith, Jr. is tasked with improving between now and the start of training camp. Mavericks head coach Rick Carlisle has also has a list of things he expects Smith, Jr. to work on.

“It’s been about efficiency,” Smith, Jr. said about his conversations with Carlisle. “He has been telling me to be efficient on both ends. Make the right plays, keep my teammates involved, and be a great leader.”

And there’s that word again: Leader. In Summer League, Smith, Jr. proved himself capable and worthy of that title. But he knows that if he wants to become a leader in the NBA, he has a lot to learn and a lot of room to grow.

“[I’ve grown] a tremendous amount,” Smith, Jr. said about his time in Summer League. “I got a lot of things to learn about the pro game. Obviously, this is my first time playing it and I think I’m taking it all in right now. I’m all ears from the hotel all the way until the game is over. So, I’m taking everything in I’m supposed to.”

If he continues to do that, his impressive athleticism may take a backseat to the leader he becomes.