Building the Castle: Spurs’ Rookie Lays the Foundation for a Bright Future

Selected with the No. 4 pick in last year’s draft, the UConn standout could be on the road to stardom in San Antonio.

Mathey Gibson | 3 Hours Ago

Sep 30, 2024; San Antonio, TX, USA; San Antonio Spurs Stephon Castle (5) photos for photos during Media day at Victory Capital Performance Center in San Antonio. Mandatory Credit: Scott Wachter-Imagn Images / Scott Wachter-Imagn Images

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San Antonio Spurs rookie Stephon Castle is quickly making his presence felt in the preseason, most recently leading the team with 17 points off the bench in a 107-97 win over the Orlando Magic on Wednesday night.

His stat line—17 points (4-9 FG, 2-5 3Pt, 7-10 FT), two rebounds, four assists, and two steals—only scratches the surface of the impact Castle is already showing, and the Spurs' coaching staff, including head coach Gregg Popovich, has to be intrigued by his early development.

Castle’s Skillset and Fit in San Antonio’s System

Oct 7, 2024; San Antonio, Texas, USA; San Antonio Spurs guard Stephon Castle (5) shoots over Oklahoma City Thunder guard Alex Ducas (88) during the second half at Frost Bank Center. / Scott Wachter-Imagn Images

Castle’s athleticism stands out immediately, especially in a system known for developing skilled, versatile players under Popovich.

His elite leaping ability and defensive potential make him a unique addition to a Spurs team that’s integrating new talent behind Victor Wembanyama. Popovich has always valued high-IQ players, and Castle’s natural instincts on both ends of the floor position him well for a significant role this season.

Castle’s ability to get to the free-throw line, as demonstrated by his 10 attempts in the game against Orlando, is a rare trait for a rookie guard. This skill is especially valuable for the Spurs, who often rely on guards who can break down defenses and create offense by attacking the rim.

His combination of quick first-step acceleration, body control, and physicality means he’s not only capable of scoring but also drawing fouls, an important asset in slowing down the game or punishing defenses for being out of position.

In Popovich’s motion-heavy offense, Castle's passing ability is also key.

He displayed great vision with four assists in his recent performance, which could become a defining part of his game.

In a system where ball movement is critical, Castle’s ability to recognize defensive shifts and find open teammates will allow him to thrive.

His evolving chemistry with big men like Wembanyama, Zach Collins and Keldon Johnson will create additional spacing, allowing Castle to either drive and kick or find the roll man on pick-and-roll plays.

The Chris Paul Factor

Sep 30, 2024; San Antonio, TX, USA; San Antonio Spurs guards Stephon Castle (5) and Chris Paul (3) pose for photos during Media day at Victory Capital Performance Center in San Antonio. Mandatory Credit: Scott Wachter-Imagn Images / Scott Wachter-Imagn Images

One of the most exciting aspects of Castle’s development is the prospect of playing alongside veteran point guard Chris Paul.

Paul’s arrival in San Antonio gives Castle a mentor who excels in half-court offense, decision-making, and defensive intensity. Paul’s floor generalship is legendary, and pairing Castle with him in the backcourt will accelerate the rookie’s growth by placing him in lineups where he doesn’t need to dominate the ball but can still attack off screens and cuts.

Defensively, Castle’s length and athleticism make him a perfect candidate to pair with Paul, whose defensive acumen often goes underappreciated.

While Paul may handle more traditional point guard duties, Castle’s ability to guard multiple positions—given his 6-foot-6 frame and quick lateral movement—will give Popovich the flexibility to switch assignments, an essential trait in today’s NBA.

The Bigger Picture: Spurs’ Rotations and Castle’s Development

Oct 9, 2024; San Antonio, Texas, USA; San Antonio Spurs guard Stephon Castle (5) dribbles against Orlando Magic forward Franz Wagner (22) in the first half at Frost Bank Center. Mandatory Credit: / Daniel Dunn-Imagn Images

Castle’s role alongside Tre Jones and Devin Vassell in the backcourt presents a variety of interesting lineup possibilities for Popovich.

Vassell, the Spurs’ best perimeter defender outside of Wembanyama, has developed into a reliable two-way player, and Castle’s presence as a slasher and facilitator could unlock more scoring opportunities for Vassell as well.

Jones, a more traditional point guard with a pass-first mentality, could complement Castle’s dynamic athleticism in staggered rotations.

However, the real intrigue comes with how Castle could play off of Wembanyama, the Spurs’ crown jewel.

In pick-and-roll situations, Castle’s ability to make the correct read—whether it’s a lob to Wembanyama or finding an open shooter like Champagnie, Johnson or Vassell—will be critical to the Spurs’ offensive flow.

Popovich’s system has always favored multi-dimensional guards who can read defenses, and Castle’s developing offensive skillset positions him to become a key part of the team’s core.

Utilizing Castle’s Defensive Potential

Jul 13, 2024; Las Vegas, NV, USA; San Antonio Spurs guard Sidy Cissoko (25) celebrates with San Antonio Spurs guard Stephon Castle (5) after scoring against the Portland Trail Blazers during the second quarter at Thomas & Mack Center. / Stephen R. Sylvanie-Imagn Images

Defensively, Castle is already showing potential to be a disruptor on the perimeter.

With his long wingspan and quick footwork, he’s capable of switching onto multiple positions, a trait that will allow the Spurs to be versatile in their defensive schemes. Popovich is likely to employ more switching defenses, utilizing Castle’s ability to guard both smaller guards and larger wings.

This defensive versatility, combined with his knack for generating steals, will give the Spurs more transition opportunities.

Popovich’s Challenge: Managing Expectations

San Antonio Spurs coach Gregg Popovich stands in front of the media before his press conference at the team's Media Day.

Sep 30, 2024; San Antonio, Texas, USA; San Antonio Spurs coach Gregg Popovich stands in front of the media before his press conference at the team's Media Day at Victory Capital Performance Center. / Matt Guzman-San Antonio Spurs On SI

At only 19 years old, Castle is still raw, but the foundation for an impact player is evident.

Popovich will likely bring him along slowly, starting the season with more bench minutes and gradually increasing his role as he becomes more comfortable with the NBA’s speed and physicality.

Given the Spurs’ track record of developing young talent, Castle is in an ideal situation to refine his offensive game, especially his shooting consistency and decision-making in high-pressure situations.

If Devin Vassell remains sidelined due to injury, Castle could find himself in the starting lineup earlier than expected.

In this scenario, Popovich would likely place him in a guard-heavy lineup with Chris Paul, maximizing Castle’s off-ball movement while letting Paul orchestrate the offense.

The Bottom Line

Oct 7, 2024; San Antonio, Texas, USA; San Antonio Spurs guard Stephon Castle (5) during the first half against the Oklahoma City Thunder at Frost Bank Center. Mandatory Credit: Scott Wachter-Imagn Images / Scott Wachter-Imagn Images

Castle is the type of high-upside rookie that the Spurs have historically thrived with.

His early preseason performances have already shown flashes of brilliance, and with Popovich guiding him, his game is likely to grow exponentially throughout his rookie season.

While there will be growing pains, Castle’s athleticism, defensive potential, and developing offensive toolkit make him a fascinating piece of the Spurs’ future alongside cornerstone talents like Wembanyama and Vassell.

For the fans in San Antonio, that’s an exciting prospect to look forward to.