In his age 26 season, Kolten Wong is finally breaking out offensively. As of this writing, his 118 wRC+ would be a career high by 22 points. His .399 on-base percentage puts him in the top twenty among hitters with at least 250 plate appearances. That OBP places him second on the St. Louis Cardinals, as does his .307 batting average.
Much of Wong’s breakout is due to his non-contact profile. He’s improved both his walk rate and strikeout rate thus far for the fourth consecutive season. That improvement is even more impressive considering pitchers have taken a more aggressive approach against him this year. Wong has seen 5.3% more pitches in the strike zone than he did last year, the third largest increase among players with 250 PAs in 2016 and 2017. Kolten Wong deserves credit for cutting his chase rate down to only 25.3% this year from 30.3% last year and 35.0% in 2015. That 9.7% drop since 2015 is the third largest decrease in the MLB (min. 250 PA in 2015 and 2017).
Wong’s steady non-contact improvement is legit. While it’s hard to see him further improving this part of his game, we can reasonably believe this reflects his true talent level. But Kolten Wong is also hitting a career best .307 with a .842 OPS. How sustainable is his success with the bat?
To evaluate Kolten Wong’s contact profile, I’ll use Statcast data hosted on Baseball Savant. While we can look at average exit velocity and launch angle, it’s best to look at these on a spectrum. Baseball Savant breaks batted balls into six types of contact quality: barrels, solid contact, flares and burners, topped, hit under, and weak.
Here’s how Wong’s 2017 compares to the MLB:
Barrels are the best contact type for the hitter (by far), followed by solid contact and then flares & burners. Together, those three categories constitute “productive” contact for the hitter. Topped, hit under, and weak constitute “poor” contact. At the surface, Wong has made about 2% less productive contact than the MLB average (which includes pitchers) and 2% more poor contact. When looking at only barrels and solid contact, Wong’s 8% rate trails the MLB average by nearly 4%.
Additionally, while each type of contact quality has some predictive value year-to-year (that is, hitters continue to make similar contact at similar rates), flares and burners are the least sticky contact type. So, if Wong is going to continue having success on contact, he’ll need to turn some of his flares and burners into barrels or solid contact as opposed to topped or hit under balls. Given that he’s been below average at generating barrels and solid contact over the past three years, it’s unlikely that he’ll suddenly start hitting them more often.
On a positive note, when Wong makes poor contact, he keeps it on the ground at a higher than average rate. Since he has above average speed (more on that soon) and generates below average exit velocity, he’s better off putting the ball on the ground than in the air. Thus, Wong is controlling his mis-hits to still put himself in a better position to succeed.
Next, we can look at the results on each type of contact quality by comparing Wong’s wOBA (weighted on-base average) to his expected wOBA (xwOBA) and the MLB average wOBA. He’s noticeably weaker than the MLB average on barreled balls, which may be partly due to a small sample size of seven barrels. However, as you can see in the radial chart above, most of his barrels barely break the threshold beyond solid contact, so we’d expect him to produce below average results on those balls. The only other wOBA differential that jumps out compared to the MLB average is on weak contact, where Wong is helped by four bunt singles.
Comparing his wOBA on each type of contact to the xwOBA on each type, we notice that Wong is outperforming his expected results in every category. While faster players are more likely to outperform their xwOBA, it doesn’t explain all the difference for Kolten Wong. After all, his 27.7 feet per second sprint speed is only 0.7 ft/s above average. Thus, we might say he’s been a bit lucky, a notion supported by his .356 BABIP.
If Wong’s wOBA was in line with his aggregate xwOBA of .326, he’d be a roughly league average hitter. While that’s better than what he’s shown thus far in his career, it’s nothing spectacular.
Lastly, despite Wong’s career year offensively, his overall value is held down by his play defensively. Wong is posting a career worst .974 fielding percentage through Saturday and is on pace for career lows in defensive runs saved and UZR. According to inside edge fielding, he’s converting “routine,” “likely,” and “even” plays at career low rates. His struggles there aren’t being offset by making harder plays either, as he’s only converted “unlikely” or tougher plays once in thirteen chances.
While these defensive metrics take much larger samples to stabilize, a 0.5 ft/s drop in sprint speed since last year suggests Wong is already losing a step. A lessened ability to convert the tougher plays coupled with his inconsistency to make the routine plays would erode Wong’s defensive value.
So, where does Kolten Wong stand in 2017? Is he really breaking out? Unfortunately, probably not. While his non-contact offensive improvement is legit, his success on-contact will likely regress. Additionally, a downward trend defensively will limit his value even if his offensive success is sustained.
From 2014 to 2016, Kolten Wong was essentially an average or slightly better second baseman due to his strong defensive play. In 2017, Wong is again a slightly better than average MLB second baseman, this time thanks to a strong offensive year. Going forward, he’s projected to be about exactly average. Value-wise, Kolten Wong is the same player as he’s always been; he’s just going about it in a different way.
Again, credit to @cardinalsgifs for the article’s artwork. If you don’t follow him on Twitter, you should follow the link and fix that now.