Apr 13, 2025; San Antonio, Texas, USA; San Antonio Spurs guard Stephon Castle (5) looks to the scoreboard during the second half against the Toronto Raptors at Frost Bank Center. Scott Wachter-Imagn Images

Stephon Castle Reveals Lessons From Gregg Popovich Before Retirement

Originally posted on San Antonio Spurs on SI
By Matt Guzman | Last updated Sep 23, 2025 8:42 PM ET

Stephon Castle got the same number of games under Gregg Popovich that De'Aaron Fox got with Victor Wembanyama last season.

A mild stroke eventually pushed the San Antonio Spurs' Hall-of-Famer to retire from the sidelines just a few games into the season, while a pair of season-ending injuries sidelined Wembanyama and Fox. Both stints proved beneficial.

Fox determined that he and Wembanyama had the makeup to be the "best pick-and-roll duo" in the NBA; Castle, meanwhile, learned to take his time.

Castle Speaks on Popovich

“I only played five, six games with Coach Pop," Castle said in an interview with ESports Insider, "but on that short scale, I feel like I learned a lot from him ... not speeding my way to things, just taking time with it and letting it come. I feel like that’s what I did last year in workouts.”

Speaking on the #Spurs two weeks before training camp, Stephon Castle made clear his confidence in his team is inviolable.

Next year, San Antonio wants to start a fire the league can't put out. And Castle wants to be a catalyst.

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— Matt Guzman (@mattgzman) September 19, 2025

From the jump, Castle impressed Popovich with his work ethic. The sizable guard was quick to listen, slow to speak and coachable.

"(He's a) really mature young man," Popovich said after one week of training camp. "Has a great demeanor and way about him ... has a good basketball IQ."

Even Wembanyama gave the then-rookie his flowers.

“I see him fitting (in) very well,” Wembanyama said. “I’ve seen exponential progression from him from one practice to the other. The way he learns is pretty impressive.”

Daniel Dunn-Imagn Images

Castle quickly embedded himself in Mitch Johnson's rotation after Popovich took his leave of absence. Having learned under UConn's Dan Hurley, the transition wasn't intimidating. Especially when he arrived with the coach's seal of approval.

"Steph is a warrior," Hurley told Spurs On SI. "He's not going to run from the expectations of winning."

Next season, Johnson's return will provide San Antonio the familiarity it needs to make Year 1 without Popovich even less daunting. The Spurs, searching for their first playoff berth since 2019, have a long road ahead of them. But their mindset won't change.

"We've tried to win every game that we've played in," Castle told Spurs On SI. "And (next season), that doesn't change."

No longer a rookie, Castle has a larger role waiting for him. But between him, Wembanyama, Fox and Mitch Johnson, a lot remains the same. He sees that as a plus.

"We still have our same core guys," Castle told Spurs On SI. "I've always been confident in the guys in our locker room. (That) confidence really doesn't change much."

This article first appeared on San Antonio Spurs on SI and was syndicated with permission.

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