Javier Baez's Dramatic Plate Discipline and Batted Ball Improvements

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Javier Baez’s Dramatic Plate Discipline and Batted Ball Improvements

Chicago Cubs

javy baez cubsJavier Baez was the smallest big story (biggest small story?) of the 2015 season. Having been among the first call-ups for this long, tiring rebuild, Javier Baez quickly left our big league radar for nearly all of last year. Of course, there was the unfortunate passing of his sister and the untimely injury at AAA Iowa pushing him further away from Chicago, but there’s no question that his importance and upside was downplayed after years of being a singular focus.

It’s not much of a surprise, though, when you think about it. This past season, the Cubs won 97 games, made it to the NLCS, and left with awards for the best NL manager, rookie and pitcher. But all of that is over now; we have to refocus on 2016, and Javier Baez might be as important as ever.

As I’m sure you’re aware, though, Baez’s absence from Chicago for most of 2015 wasn’t entirely out of his control. His 2014 call-up didn’t go as hoped, even if it did ultimately go as expected. As a 21-year-old middle infielder in the Major Leagues, Baez’s weaknesses were immediately exposed. Over 229 plate appearances, he struck out an historic 41.5% of the time. Although his power was mostly there – 9 HRs, 6 2Bs .155 ISO – his crippling strikeout rate dampened any offensive potential.

Worse, his issues appeared to be stemming from multiple areas. For example, while some players struggle with pitch recognition and others struggle to make contact, Javier Baez was struggling with both. His plate discipline data – which I’ve previously defined, here and here – suggested exactly that.


O-Swing% Z-Swing% Swing%

’14 Javier Baez

41.0% 58.7%


’14 MLB Average 31.28% 66.29%


Starting from the left, the 2014 version of Javier Baez had an O-Swing% that was ten percentage points higher than league average. He was much more likely than the average player to swing at a ball. Over that same stretch, his Z-Swing% was eight percentage points lower than average. He was much less likely to swing at a strike in the zone than the average player. In 2014, Baez wasn’t swinging at strikes enough and was swinging at balls too often. Clearly, Baez was guessing often and guessing poorly.


O-Contact% Z-Contact% Contact%

’14 Javier Baez

42.1% 77.5%


’14 MLB Average 68.73% 88.86%


But the problems didn’t end there. As we can see, there’s still the other half of his issue to consider: contact rate. In 2014, Baez’s O-Contact% was twenty-six percentage points lower than the league average. It’s not always a good thing to make contact with pitches out of the zone, because that can often lead to weak contact, but clearly he wasn’t even capable of doing so if he wanted to. Worse, his Z-contact% was eleven percentage points lower than average. His overall contact rate was twenty-two percentage points lower than the average player. In the zone, out of the zone, it didn’t matter. The 2014 version of Javier Baez could not put his bat on Major League pitching. [Brett: To put it in context, among all players with at least 200 plate appearances in a season, Baez’s 2014 contact rate was the third worst since 2000.]

All of those problems combined to create his 19.2 swinging strike percentage and 41.5% strikeout rate. But Javier Baez is an extraordinarily talented and hardworking baseball player, so, despite the pessimism, you just knew this wasn’t going to be the last we heard of him. Check out the charts below to see the 2015 version of Javier Baez, as compared to his 2014 self and the league averages (229 plate appearances in 2014, 80 in 2015, so grains of salt).


O-Swing% Z-Swing% Swing%

’14 Javier Baez

41.0% 58.7% 47.9%
’15 Javier Baez 40.2% 68.2%


’15 MLB Average 31.80% 67.65%


So then, by my count, Javier Baez improved in every single plate discipline category across the board. Let’s break this down one by one, and see how much better he was in 2015. Starting from the left, you’ll find his least improved upon area, O-Swing%. Although he did improve by about one percentage point, he clearly still needs working laying off pitches out of the zone. However, the very next category, Z-Swing%, is extremely encouraging. Over what amounted to just half a season of development in the minors, Baez was able to increase his recognition of pitches thrown in the zone by 10 percentage points and got it to above league average. That is very impressive in its own right, but to do it in such little time is on another level. If he can continue to improve his O-swing% he can quickly become an average to above-average pitch recognizer (?) soon.


O-Contact% Z-Contact% Contact%

’14 Javier Baez

42.1% 77.5% 59.0%
’15 Javier Baez 48.6% 83.0%


’15 MLB Average 67.47% 88.18%


Just like before, the improvements don’t end there. Javier Baez was able to very successfully improve upon his contact rates, as well. He is now making more contact, by about six percentage points more, on pitches both in and out of the zone. By doing so, he raised his overall contact rate by eight percentage points, up to 67.7%. Although he is still a good deal below average, he 1) is never going to be the best in the league, but 2) has made very significant strides in such a short amount of time. Given how young Baez is and how well he’s been able to adjust so far, you can’t help but re-open the dreams of his immense upside.

Due to the striking improvements across the board in both pitch recognition and contact rates, Baez was able to lower his swinging strike percentage to 16.4% and his overall strikeout rate to a much more manageable 30.0%. The best part, though, is that we’ve only begun to scratch the surface. Indeed, Javier Baez’s improvements in batted ball data are almost equally impressive to his plate discipline. Take a look at the chart below …



13.7% 41.0%


2015 31.4% 37.3%


Starting with the type of ball he put in play, Javier Baez once again improved across the board. He was able to increase the number of line drives he hit at the expense, primarily, of fly balls. By lowering his ground ball rate by four percentage points and his fly ball rate by fourteen percentage points, Javier Baez hit more than double his line drive rate from his rookie season. That is going to translate to more hits, more power, a better average and a more productive offensive player.

Pull% Cent% Oppo%


48.3% 31.4%


2015 32.7% 34.6%


Continuing the trend, Javier Baez improved the ultimate location of the balls he put in play, once again, across the board. In 2015, there was nearly a 50% chance that Javier Baez was going to pull the ball. That type of split allows pitchers to attack you differently and defenses to defend you differently, which can further depress any offense that you may have otherwise produced. In 2015, though, Javier Baez became a different hitter. He used every field at almost the exact same rate. By resisting the urge to pull the ball so often, Baez was able to spray his hits across the field in every direction. With that ability, defenses can’t shift and pitchers have to be especially careful with where they leave their pitches. I can’t think of many conversations discussing his field usage before, but this is certainly a welcomed, if unexpected improvement.

Soft% Med% Hard%


18.6% 50.0%


2015 7.7% 59.6%


Last, but certainly not least, we come to the Stat Du Jour – Quality of Contact. There’s been an increasingly large amount of attention drawn to quality of contact (and exit velocity) of late, but that’s because it can have a pretty significant correlation to actual and expected performance. And as you can see in the chart above, Javier Baez once again improved on every single one these stats. He lessened his soft contact rate by an impressive eleven percentage points, while increasing his medium contact rate by nearly ten percentage points and his hard contact rate by one percentage point. Like using the entire field, this type of improvement will improve his overall line in an underlying, season-long way.

So, in the spirit of recapping a recap, I want to deliver to you in short form, the improvements made by Javier Baez from 2014 to 2015 because they are just so impressive:

  • Swung at fewer pitches out of the zone,
  • Swung at more pitches in the zone,
  • Made contact with more pitches out of the zone,
  • Made contact with more pitches in the zone,
  • Decreased his swinging strike rate,
  • Decreased his strike out rate,
  • Hit more line drives,
  • Hit fewer ground balls and fly balls,
  • Hit more balls to center and right field,
  • Hit fewer balls to left field (pulling it),
  • Decreased the rate of soft contact, and
  • Increased the rate of medium and hard contact

By the end of the season, Baez finished with a .289/.325/.408 slash line while playing third base, shortstop and second base – all seemingly above average. He runs the bases well, he has excellent baseball instincts, and he is still just 22 years old. Javier Baez has a lot of baseball ahead of him.

Don’t get me wrong. Improvements are great, but he is still well below average in many areas of his game. However, witnessing such drastic improvements in such a wide array of statistics in such a short amount of time is impressive. This young man already displayed the will and desire to improve, but now we know that he can. I look forward, very much, to seeing what Javier Baez can do in 2016.

And, hey: today’s his birthday.

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Author: Michael Cerami

Michael Cerami covers the Chicago Cubs, Bears, and Bulls at Bleacher Nation. You can find him on Twitter @Michael_Cerami