Here’s what I know about Dion Waiters, the No. 4 overall choice by the Cavaliers in the NBA Draft.

He can fill it up.

He was a green-light shooter at Syracuse, a guy who would fire even when he had a bright yellow light. He has range. He’s an athlete.

He has the makings of a really good NBA player. He’s young, and most fans are surprised by the pick, and he didn’t start in college, so we’ll see.

We’ll see with everybody in this draft. In every draft.

The fact he didn’t start at Syracuse raises eyebrows, but it shouldn’t necessarily raise red flags. Syracuse was loaded. Jim Boeheim is Jim Boeheim. That was his role.

When Waiters came into the game, everybody stopped. The other team adjusted — or tried to. I saw it multiple times.

He was a weapon.

The Cavaliers needed a wing. They needed a young scorer, someone with star potential. Waiters has it.

He’s 6’4, which is smallish for an NBA shooting guard. He’ll have to adjust to the NBA, to the spotlight, to a role. Kyrie Irving will help that.

Waiters is not a sure thing. He’s going to have to create his own shot, play in Byron Scott’s system, prove he can defend. In college, he carried himself and ran the floor like a pro.

Again, we’ll see. With every pick.

I’ll never forget in the minutes after Ohio State beat Syracuse in the Elite Eight in Boston last March seeing Waiters in the tunnel. He was crying, basically uncontrollably, when he hugged someone — presumably a Syracuse trainer or administrator. Waiters was crying so hard that this person he was hugging had to hold him up.

It was March. It happens.

It wasn’t 36 hours later — it might not have been 18 — that I saw Waiters had declared for the NBA Draft.

It happens.

Now, he’s a Cavalier. Now, he has to prove himself. He has Irving to help. He’s going to have the green light — to some extent.

The Cavaliers need him to be great. I think he has the tools to be great.

It will take time. He’ll need help.

We’ll see. As always.