To help answer that question, let's compare Ionescu's performance at Oregon to that of other top WNBA prospects from recent years using advanced statistics.
The biggest strengths
Ionescu led Division I in assists per game as a senior and was second behind Ivy Wallen of North Alabama in her rate of assisting teammates' baskets,according to HerHoopStats. So it's no surprise her assist rate is at the top of her list of statistical strengths. Still, in terms of assists per 100 team plays, it's somewhat remarkable that Ionescu has the best rate of any future WNBA player in my database -- which includes all future WNBA players since 2009-10, most of their senior seasons dating back to 2003-04 and a few individual seasons before that.
For the most part, assist rate has translated well to the WNBA, as reflected by players' assist rate over their first four seasons as pros. (All "WNBA" rates will cover their first four seasons to have a level playing field for players midcareer.)
Courtney Vandersloot, the previous leader in college assist rate among future WNBA players, is the league's all-time leader in assists per game and has led the league in this category each of the past three seasons, as well as in 2014. Temeka Johnson led the league on a rate basis each of her first two seasons and actually had a better assist rate over her first four seasons than Vandersloot.
Of course, assists were only part of the equation as Ionescu became the Division I career record holder (men's or women's) with 26 triple-doubles at Oregon. Statistical analysts generally measure this kind of well-rounded play with the "Versatility Index," which multiplies points and assists per 100 team plays and rebounds per 100 opportunities and takes the cube root of them to reward balance.
Predictably, Ionescu dominates this leaderboard, with three of the top six years among future WNBA players and far and away the best Versatility Index of the group as a senior. Of these players, only Maya Moore fully translated well-rounded play to the WNBA, where to varying degrees they specialized more. But Ionescu is so far ahead of everyone else, that precedent might not be meaningful for her.
The 'strength' that might be a weakness
While Ionescu shot 42% from 3-point range as a freshman, it took her four years in college to become equally efficient inside the arc. She made just 37% of her 2-point attempts as a freshman and dipped a bit to 45% as a junior before surging to 59% this season, one of the best marks for a WNBA-bound point guard.
Accuracy on 2-pointers doesn't translate particularly well to the pros, and that has especially been the case for the other players on this list. Kelsey Plum, the No. 1 overall pick in 2017, has made better than 37% of her 2s just once in her first three seasons -- a key reason Plum has fallen short of expectations. At a listed 5-foot-10, Ionescu is taller than the other point guards on this list, but it wouldn't be terribly surprising if she struggled to finish early in her career.
The 'weakness' that might be a strength
As a senior, Ionescu actually saw the share of the Ducks' plays that she finished with a shot attempt, trip to the free throw line or a turnover decline to the lowest mark of her four-year career. Typically, No. 1 picks dominate their teams' offenses, putting Ionescu in the bottom third of top picks in my database.
Intriguingly, there doesn't seem to be much relationship between this category and how effective No. 1 picks are in the WNBA. In fact, this group of mostly UConn players was unusually successful in the pros, with four of the seven other players developing into MVPs. The ability to excel without dominating the offense might be a positive indicator for Ionescu's pro prospects.
Two true weaknesses
Looking at the same group of players as the previous leaderboard does yield a more legitimate concern: Ionescu's rate of free throw attempts also dropped as a senior. Only during her sophomore season did Ionescu complete even 10% of her plays with a trip to the line, and none of the No. 1 picks had a free throw rate nearly as low as Ionescu's as a senior.
On the plus side, this group generally got to the line as frequently or more as pros. Still, if Ionescu's 2-point percentage tumbles in the WNBA, she'll need a steady rate of free throw attempts to buoy her efficiency -- particularly given Ionescu is such an excellent foul shooter, peaking at 92% as a senior.
Aside from rebounding, Ionescu hasn't made the same impact on the defensive end as she has on offense. That shows up statistically most clearly in her rate of steals per 100 team plays, which is on the low side for a point guard drafted in the first round. (There are 26 total such players in my database.)
For the most part, the players on this list have struggled defensively in the WNBA, though that hasn't prevented Kristi Toliver from becoming one of the league's best point guards. Ionescu's size should be a plus here, too, but given the underrated value of steals, it would be nice to see her improve in this category, using her ability to see plays develop.
Despite those concerns, this look at Ionescu's advanced stats suggests she's not just the top prospect in this year's draft, but one of the best to come into the WNBA in recent memory. Over the past decade, I'd put her among the top five prospects, along with fellow No. 1 picks Brittney Griner, Maya Moore, Breanna Stewart and A'ja Wilson. Even if Ionescu doesn't dominate across the board as she did at Oregon, her versatility will give her plenty of ways to impact a game.
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