3 San Antonio Spurs players with the most to prove next season

Spurs player 2: Lonnie Walker IV
Lonnie Walker, in my opinion, is right on the cusp of becoming a very good player for the Spurs, particularly on offense. In fact, I think he has the potential to eventually take over as the Spurs' starting shooting guard over Derrick White, but he's not quite there yet.
One of Lonnie's biggest issues on the court that became abundantly clear to me as the season went on is that he simply doesn't have the ball in his hands very much. Advanced statistics confirmed this suspicion, as he trailed eight other Spurs players in touches per game, while simultaneously leading all Spurs players in points per touch. This issue should already be somewhat alleviated next season as it's likely that at least one or two of the Spurs' veteran players will be leaving the team.
Lonnie is far from being free of criticism though. What Lonnie will need to prove to the Spurs front office is that he's capable of learning some of the more subtle nuances of the game, particularly on the defensive end of the floor. While Lonnie seems to have endless athleticism, great shooting form, and flashes of very good on-ball defense, he'll need to start learning more about overall team defense, rotating, fighting through screens, and how to move off the ball on offense.
Learning these nuances and becoming a higher IQ player is what will determine whether he's a long-term piece of the Spurs' young core or if he's expendable. Unlike Šamanić though, Lonnie seems to already have a decent foundation of both skill and athleticism that he can build upon. This is precisely why I will be expecting a lot from him next season.