What made Devin Vassell more valuable to the Spurs?
Team fit clearly didn't matter to Brian Wright in making his first draft selection as the Spurs' general manager, meaning the team simply thought of Vassell as the more valuable player, even if just by the slightest margin. So now that we understand the differences in Haliburton and Vassell's roles in their first two seasons, the next question to ask is: "what can Vassell bring to the Spurs now and in the future that Haliburton may not be able to?"
Defensive versatility
Despite some limitations, Tyrese Haliburton is a very impressive defender in his own right. He has an incredible feel for the game on both ends of the floor and uses it to his advantage, reading plays quickly and jumping in passing lanes for steals. At 1.7 steals per game last season, he came in 2nd place only behind Dejounte Murray for most steals in the league.
With that in mind, however, Haliburton's defensive impact is felt almost exclusively away from the ball. He'll certainly disrupt plays and grab steals (and a lot of them), but he isn't someone that can necessarily be trusted as a help defender around the bucket, his size makes him a bit vulnerable to die on screens, and he won't be defending multiple positions on-ball at the point of attack.
On the other hand, while Devin Vassell may not grab quite as many steals (for now), he can effectively do all of the things mentioned above on the defensive end. He was, in my opinion, the most polished, game-ready defender to come out of the 2020 draft class and is capable of playing on and off the ball. If the goal for the Spurs of the future is to adopt a switching scheme, having wing defenders that can effectively guard several positions on the perimeter and play disciplined off-ball defense is incredibly valuable. Vassell, even right now, has a clear edge over Haliburton in this department.
Athleticism
Vassell is and likely will be the more complete defender compared to Haliburton moving forward in part because of his athleticism. He was already quite fluid for his size coming into the league, but he has gotten noticeably bigger since his rookie season which will be key for him when guarding up a lineup on defense as well as taking contact around the rim in general. At only about 185 pounds, despite his comparable length, Haliburton's lack of strength will likely continue to diminish most of his value as an isolation defender against three, if not four positions.
Vassell's vertical leaping ability also gives him a noticeable edge on both ends of the floor. When defending drivers, if a player is able to make it past Vassell's quick feet, he's still able to recover and go for the block from behind. When away from the ball on defense, this leaping ability also allows him to be an effective help-side shot blocker. On the other side of the floor, Vassell gets noticeably more lift on his jump shot compared to that of Haliburton, and in tandem with his uniquely high release point, his jumper is difficult for many to defend.
Rim pressure
This last point is still more theoretical than something that's been fully realized, but if Vassell's added strength becomes functional to the point that he can finish strong around the rim, this could help to unlock the rest of his scoring package.
Coming into the league, finishing at the rim was one of Vassell's biggest areas for improvement as he struggled with contact. Because bigger defenders made him vulnerable to taking bad angles on drives, he often settled for tough midrange jumpers instead. In the NBA, this allows defenders to comfortably put more pressure on him on the perimeter rather than sagging off of him, making it more difficult for him to get a shot off despite the good rise and release point on his jump shot.
But Vassell is a better jump-shooter than his stats suggest and is comfortable hitting threes and midrange twos off the bounce. If defenders begin thinking of him as a threat off drives as well, they'll be forced to sag off of him to prevent those drives, meaning he'll have even more space to get those shots off.
While Tyrese Haliburton will mostly have to rely on space creation and good touch to be efficient around the rim, though, Vassell could conceivably use his length and superior athleticism to finish above the rim, even through traffic. Vassell would be wise to take a page out of Keldon Johnson's book to improve that part of his game.
If Vassell can consistently use his defensive versatility and athleticism to his advantage while also beginning to put more pressure on the rim, we could be looking at a fundamental piece of the Spurs' core for years to come. If he goes above and beyond, I don't think the NBA's Most Improved Player award is out of the question for him either.