Jonathan Isaac is the best big man in this draft class
Isaac is typically thought of as a relatively high-floor low-upside 3&D prospect. It is easy to fall into this trap when looking at Isaac. He has good defensive tools and production, some shooting success, and doesn’t offer too much else on the offensive end. As is often the case, draft writer Kaiser Lindeman forced me to look at Isaac in a different light. A closer evaluation of his film and statistical profile revealed that he has a unique combination of strengths, and his upside is being undersold.
General perception of Isaac as a “wing” is in many ways what led to him being underrated. Brandon Ingram’s existence is arguably another reason. Florida State played Isaac as a power forward all year, much like Ingram at Duke last year. Both are gangly and fluid athletes who seem like they should be similarly good on the defensive end. A quick look at their respective defensive production should at least cause us to raise our eyebrows at such an assumption.
The purpose of this chart is not to illustrate that Ingram was a bad defender. He was a fine defensive prospect for a wing (though probably a bit overrated). What should become apparent is just how strong Isaac’s defensive production is. When you consider his rebounding and shot blocking he doesn’t look like a good wing defensive player, he looks like a good *big man*. If Isaac can provide the perimeter versatility of a wing while doing traditional power forward things at a high-level, it completely changes the calculus on his defensive upside.
A look at Isaac’s film from this year more than backs up his numbers. Unlike many wings who rack up solid block numbers, Isaac doesn’t fly in from the weak side to swat guys shots. K.J. McDaniels, Aaron Gordon, and Miles Bridges are all examples of this type of back-side rim protection. What Isaac brings to the table is far more valuable. He instinctually rotates to the rim in help situations and uses verticality well to bother shots. Being 6'10 with a 7'1 wingspan, he is able to alter a lot of shots at the rim that he doesn’t get credited with a block on. Plays like this are commonplace in both transition and half-court situations.
In on-ball situations, Isaac is able to bother shots that are typically converted by the offensive player.
Isaac uses that same length and positioning to rebound at an excellent rate for a power forward, or even a center. When you consider team context at Florida State, Isaac’s numbers only become more impressive. They play three guys who are all more “traditional” big-men than Isaac heavy minutes (Michael Ojo, Koumandji, and Jarquez Smith), and Ojo and Koumandji are 7+ foot behemoths who can rebound and block shots at a high level. Theoretically, on an NCAA team with average interior defenders Isaac’s numbers would be even more outlier good.
The biggest flaw in Isaac’s interior defensive profile is his skinniness. There have been really successful skinny big man defenders (cough Nerlens Noel cough), but Isaac’s frame is still an issue. At this stage, he is simply not equipped to guard the NBA’s true power players. The good news is all that really does is prevent him from playing Center, because aside from Blake Griffin, Paul Millsap, and maybe a few others, there aren’t many offensively dominant “power” 4’s.
If anything, since Isaac is a quick-leaper with length and timing he has real upside to eventually play the 5. According to his DraftExpress measurements, he’s already gained 20 pounds in the past two years. If he can add another 20 and get himself to be about 225 it is easy to see him spending some time at the 5.
The reason you would want to play Isaac at the 5 is the devastating versatility it could unlock in a defense. In addition to being good at “big-man things,” Isaac is also a talented perimeter defender.
His short area quickness and reactive ability is about as good as I’ve ever seen in someone his size. Watch his footwork here as he completely cuts off Jayson Tatum’s penetration.
There aren’t many 6'10 guys in the league who can move their feet like that. Isaac’s package of lateral quicks and insane length allows him to make some pretty impressive on-ball defensive plays. Here he is destroying another NBA wing prospect (Justin Jackson) in Kawhi-esque fashion.
That short area quickness also allows Isaac to get around screens exceptionally well for a player of his stature. Now, Isaac is by no means a perfect defensive prospect. He gets beat off-the-dribble a decent amount. Importantly though, the times he gets beat are almost always due to him gambling for a steal, him not having the strength to cut a guy off, or not having the lateral speed to keep up with someone over distance.
That last quality, his speed over long distances, is odd for someone his frame. Usually guys who are long like him can move laterally to keep up with guys but struggle to respond to guys in short areas. Isaac is the opposite. Thankfully, containing guys in small areas is much more relevant in the NBA because help defense prevents guys from being stretched out too much.
Off-the-ball, Isaac does have issues with consistency. He seems to drift at times, and there are questions about his competitiveness. Since he also displays moments of high-instinct rotation and his bottom-line impact is so good these concerns aren’t giant, but are worth thinking about.
With his flaws in mind, I don’t see Isaac as a truly game-changing Kawhi/Draymond level defender. However, given his versatility as a plus perimeter and interior defender Isaac profiles as both a high-floor and high-upside defensive prospect.
The guy Isaac reminds me most of as a defensive prospect is actually Kevin Durant. Durant obviously has a similar frame, but his BLK/STL/REB numbers in conjunction with perimeter quickness is really strikingly similar.
Going by most +/- metrics like RPM, Durant has only been about a +1 defender in the NBA, not an elite guy. So why I am so high on Isaac’s D?
Well, basically, Durant *could* be an elite defender. In order to preserve his body and maximize his offensive value Durant has played his NBA career at the 3, and probably not expended maximum effort on the defensive end.
Last year’s playoffs showed that when engaged, Durant can be one of the league’s best defenders. He played most of his minutes at the 4, and totally disrupted the Spurs and Warriors offense with his ability to switch and guard on the perimeter along with protecting the rim.
Even if Isaac doesn’t have quite Durant’s raw athleticism, he should be a much more consistently great defender in the NBA. Unlike Durant, he will hopefully be played primarily at the 4, and since he isn’t an offensive super star he will be able to dedicate himself to wreaking havoc on the defensive end.
In all, Isaac is a pretty high-floor defensive prospect regardless of situation. If a coach does utilize him correctly and plays him at the 4 and 5 he has legitimate All-NBA defensive upside. I don’t think most view Isaac’s defense this way, but I think it’s time to start asking people why not.
When you consider Isaac a true-4 and possible 5 defensively, his offensive profile also becomes all that more enticing. Seriously, why does Lauri Markkanen get the (offensive) benefit of being called a stretch 4/5, while Isaac, who also stretches the floor and is better at actual big man defensive things, get labeled a wing?
Isaac is not a good offensive prospect for a wing. His shot is a real question mark, and he’s not great at attacking off-the-dribble or reading the floor. Those weaknesses look completely different when you consider him as a true 4/5, but still should be evaluated.
Even as a 4/5 a bad shooting outcome would tank his value as a player. Predicting shooting is pretty much impossible, but there are reasons to believe in Isaac’s shot. Shooting 78% from the free throw line is a big deal. His comfort and frequency shooting off-the-dribble pull-ups is also a good sign. He’s probably going to be a solid 35–38% shooter from the NBA three.
There even is upside for him having a shooting season like Otto Porter this year, or some of Trevor Ariza’s best. Right now he doesn’t do a good job of prepping for his shot and thus doesn’t shoot in high volume. Given his high and fluid release it’s possible he could turn himself into a high-volume guy with more consistent pre-catch fundamentals.
Isaac is never going to be a primary, or even secondary, offensive creator. His handle and feel for creating just aren’t there. That doesn’t mean he can’t be a useful 4th option on an offense. He’s an unselfish ball-mover, he’s got a good first step, and as he adds strength he should be very capable of attacking off one or two-dribbles and finishing at the rim. The fact that he can also pull-up fluidly in the mid-range is a plus, and prevents defenses from playing him like a non-threat.
Isaac has also shown flashes of being able to run side pick-and-roll in a pinch. He can be a bit robotic with his reads at times, which caps his upside as a creator, but he is perfectly able to execute weak-side action for an NBA team.
Many people have pointed at Isaac’s poor assist rate (7.5%) in the context of his turnover rate (13.3%) as a big flag in his profile. Compared to the other freshman wings, Isaac doesn’t come out very well in this respect. This argument is flawed though because it ignores usage context. Players only get assists or turnovers when they use possessions, so it is much more useful to look at their assist:usage (Assist%/USG%) or TO:usage (TOV%/USG%) numbers. Raw assist:turnover ratio can also be useful in evaluating a player’s decision making ability.
Isaac is clearly the worst of the group. Both in terms of taking care of the ball and creating for others. That is why he profiles as a 4th option offensively, and not a secondary creator. Nonetheless, his numbers look less bad when usage is accounted for. As mentioned, he is often mechanical in his reads and ends up throwing the ball away. These issues put a ceiling on his offensive role, but aren’t as damning as they’re sometimes thought to be.
It is also worth mentioning how good Isaac is at “role-player things” on the offensive end. Even on lower usage you don’t post a 59.3% 2P% as a wing in a power conference without doing something right. Isaac is a good offensive rebounder and a fantastic cutter. A cut like this requires a lot of instincts, and Isaac made a bunch of plays like this in the games of his I’ve seen.
Isaac’s cutting ability is another reason I’m more optimistic than most on the development of his off-ball awareness on defense.
It is crucial to evaluating Isaac’s offense to understand that he will (hopefully) be playing power forward or center. As a wing, Isaac would profile as a below-average, but not terrible, offensive prospect. As a big guy, if his shot doesn’t fail him he is a versatile floor spacer and finisher who can attack closeouts and keep the offense moving.
One player I think it’s interesting to compare Isaac to is Robert Covington. Covington was a similar stud in terms of stocks and rebounds in college. Though Isaac was definitely more impressive because his defensive numbers as a freshman at Florida State were as good as RoCo’s as a senior at Tennessee State.
Anyway, Covington has been a borderline top-20 player by RPM this year, largely due to his defensive impact. RPM certainly overrates Covington, but he is also unquestionably a high-impact NBA defender. Isaac and Covington are similar defenders in that neither are overwhelming athletes, but they both have incredible hands. Covington’s court awareness is better, but Isaac offers more as a rebounder and interior defender as well as having better feet to contain guys.
Basically, it is not hard to construct an argument that Isaac could be just as good as Covington as a defender, if not better. On offense, Covington was a much better shooting prospect, but Isaac is far more advanced in the rest of his offensive game. Covington hasn’t even shot the ball well in his great season this year and is playing at the 3, so it’s fair to say Isaac could be significantly better than what Covington has been on offense.
The point I’m trying to get at here is that Isaac has the chance to be noticeably better on both ends than Robert Covington, and Covington, though overrated by metrics, is one of the more underrated players in the NBA.
This piece has been about all over the place so I’m going to try and end on a few concluding thoughts.
- Isaac is being discussed as if he were a good wing defender with the capability of sliding down a position, much like Harrison Barnes. Instead, he should be thought of as a good interior defender with the versatility to guard on the wing. Such a designation completely changes the way he’s viewed on both ends of the floor.
- On defense, Isaac has the potential to be an all-NBA level defender at the power forward due to his versatility. He provides much more interior defense than a small-ball wing, and is as versatile a perimeter defender as almost any big in today’s NBA.
- On offense, Isaac is not a great prospect as a wing, but when thought of as an athletic stretch 4 who can shoot some, attack off the bounce, and finish around the rim he looks a lot more appealing. He will never be a star on this end but he could easily be a +1 or +2 guy with a good shooting outcome.
- If Isaac does add the strength to play the 5 near full-time his upside only magnifies. At the 5, he would be a below average interior defender but an exceptional perimeter one, and would also gain even more value on the offensive end. Given his status as a late-grower and the weight he’s added this possibility is not out of the question.
- My three reasons for skepticism of my own evaluation of Isaac are 1) What if he’s played like a wing 2) What if his shot fails and 3) Am I underrating how poor his BBIQ/on-court “fire” is. If he goes to a bad organization his future looks a lot different, he needs the right situation. Having a coach play him at the 4 is not all that difficult though, so it doesn’t affect my pre-draft ranking of him. His shot is by far the biggest variable in his future, but the same could be said of every prospect. I’m buying his shot being good enough to make him useful. Again, I’ve seen enough indicators of good IQ/competitiveness that I’m buying, but he has had some games (like their elimination game against Xavier) where he looked terrible in this respect.
Worries aside, I am super high on Jonathan Isaac. I think he’s got real +2 O/+3 D upside if played at the 4, and upside even beyond that if he can play the 5. He’s also not purely an upside pick because there are a lot of intermediate scenarios where he could be a useful ~+0.5/+1.5 starting power forward. The flexibility he offers in line-up construction makes him easy to envision on a championship contender. I see a lot of reasons to buy Jonathan Isaac, and since I’m not super high on any of the other wings in this class (more to come on this soon) — he is the #1 wing (and big) in this class for me, and my #3 prospect behind Ball and Fultz.