For fans, the excitement surrounding Stephon Castle is hardly new. From the moment he entered the league, the former UConn standout looked like someone capable of making an immediate impact.

But what Castle appears to be developing now could be something considerably more dangerous.

The 2025 Rookie of the Year has already established himself as one of the most intriguing young guards in basketball. He brings size, physicality, defensive intensity and playmaking ability, while his competitive nature has never really been questioned.

The bigger question is just how good he can become offensively.

And that is where things could get very interesting.

Castle’s 2025-26 campaign provided plenty of evidence that his offensive development is moving faster than many expected. He finished the season averaging 17 points, five rebounds, seven assists and one steal per game, while shooting 47 percent from the field and 33 percent from three-point range.

Those numbers are impressive on their own.

But the circumstances surrounding them may be even more important.

Castle was not initially expected to become the primary engine of San Antonio’s offense. The plan was closer to having him operate alongside other creators and make his impact without constantly controlling the ball.

Instead, the Spurs increasingly trusted him with the responsibility of initiating their offense.

Castle responded.

His improvement as a shooter could ultimately be the development that changes his entire trajectory. Defenders can no longer comfortably sag off him and dare him to shoot. Even a respectable three-point threat forces opponents to defend him differently, creating additional space for him to attack.

That could unlock another level of his game.

Castle has already shown he can get downhill, absorb contact and finish around the basket. He has also demonstrated flashes of a mid-range game and the ability to punish defenders who close out too aggressively.

Suddenly, the profile is becoming much more complete.

And there is one comparison that makes this development particularly fascinating.

Is San Antonio watching another Kawhi Leonard-style transformation?

It would be premature to suggest Castle is destined to become another Kawhi Leonard.

But there are certainly similarities in the developmental path.

Leonard entered the NBA primarily known for his defense and physical tools before gradually transforming himself into an elite offensive player. His shooting improved, his ability to create off the dribble expanded and his confidence with the ball grew dramatically.

Castle appears to be following a somewhat similar blueprint.

His defensive instincts were already evident when he entered the league. His physicality allows him to defend multiple positions, while his size gives him advantages against smaller guards.

Now the offensive pieces are beginning to arrive.

What makes Castle particularly difficult to project is that he doesn’t need to dominate possession to influence a game. He can cut, screen, attack offensive rebounds and finish plays without the ball. At the same time, he is increasingly capable of taking over possessions when the Spurs need someone to create.

That versatility could become one of his biggest weapons.

Imagine that player eventually developing into a consistent 20-to-25-point scorer while maintaining roughly seven assists per game and producing All-Defensive-level impact.

That would not simply be a promising young guard.

That would potentially be a franchise-level offensive option.

And the rest of the league would have another problem to deal with because Castle is not developing in isolation.

He is doing it alongside Victor Wembanyama.

The possibility of Wembanyama commanding defensive attention while Castle attacks the resulting gaps is precisely the type of pairing that could become extremely difficult to contain. If Castle continues improving as a shooter and creator, opponents could eventually find themselves choosing between giving Wembanyama more room or allowing Castle to attack one-on-one.

Neither option sounds particularly appealing.

Nobody doubted Castle had the talent to become a good NBA player.

The intriguing part is that his current development may be pointing toward something considerably bigger.

The Rookie of the Year label could eventually look like only the beginning of his story.

If his offensive evolution continues at this pace, the Spurs may have found something far more valuable than a talented young guard.

They may have found another star capable of changing the entire ceiling of their team.