Boston Red Sox starting pitcher Daisuke Matsuzaka pitches against the Texas Rangers in the first inning of their MLB American League baseball game in Arlington, Texas, August 15, 2010. REUTERS/Mike Stone (UNITED STATES - Tags: SPORT BASEBALL)

It’s hats-off time to Boston’s favorite failure, Daisuke Matsuzaka, for eclipsing the 100 IP mark this season — and doing so in commendable fashion.

Perhaps “Boston’s favorite failure” is a bit harsh on the man, but it’s difficult to separate his past four seasons from the other-worldly expectations following his acquisition leading up to the 2007 season.

But that’s a separate discussion — and ongoing one since at least 2008, when he was walking 5.05 batters per nine innings — and not the topic of this post.

17 GS, 103.1 IP, 4.09 ERA, 4.458 Expected ERA

Not too shabby.

And, when expectations of stardom and grandeur are left out of the equation, Matsuzaka has been a more than acceptable fourth starter.

Still, while Daisuke’s 2010 campaign has seemed nothing out of the ordinary, the pitcher has actually shown some considerable development this season toward improving his walk rates.

Daisuke’s Lack of Control

For years, Daisuke’s lack of control has been the bugaboo of analysts nationwide — his career 4.26 BB/9 rate undermining otherwise excellent stuff and occasionally brilliant performance.

That “lack of control,” however, has been somewhat misleading given the classical interpretation of the term. Most equate control and walk rate as being synonymous: pitchers who can locate balls in the strike zone will have good walk rates and vice versa. Therefore, since Matsuzaka walks a large number of batters, he must have poor control.

However, the relationship between walk rates and command is, in fact, far more complex than just throwing pitches in the zone. Rather, it is an interaction dominated by two factors: location, and, more clandestine, inducing swings outside of the zone.

The funny part is, Matsuzaka represents the dichotomy between the classical definition of control — a pitcher’s zone percentage — and the interpretation of that skill — a pitcher’s walk rate. In fact, Daisuke is quite adept at locating pitches in the strike zone, but fails to limit free passes. Up until 2010, this could be blamed upon his low O-Swing percentages, which resulted in far higher walk rates than the rest of his plate discipline indicators would suggest.

Walks and O-Swing Percentages

Back in ’08, Daisuke threw 51.2 percent of his offerings in the zone. A fair mark at the time, his total was just about league average among qualified starting pitchers in 2008, while it would have been among the Top 10 in ‘10.

That said, it’s funny that so many of us (myself included) consider Matsuzaka to have such bad command when, in fact, his “command” has never been particularly poor. Until 2010, batters just hadn’t chased his offerings out of the zone — and it’s difficult to understate the effect of that deficiency.

To quantify the full effect of his improved O-Swing percentage, the difference of 8.5 percent between his 2008 rate (20.7 percent O-Swing) and his 2010 rate (29.2 percent O-Swing) is nearly a full walk per nine innings, totaling 0.914 BB/9. As for where it counts — runs scored — his expected ERA would drop 0.458 runs, from 4.873 to 4.415 with the prescribed change in O-Swing percentage.

While analysts the world over (rightfully) point to zone percentage as the primary mover in walk rates, O-Swing is just as important — albeit grossly underreported.

But it shouldn’t come as any surprise. The effect of a swing on a pitch outside the zone is rather profound. Instead of the pitch resulting as ball, which it would have in the event of a no-swing, it instead becomes a strike or a ball-in-play — either ending or changing the complexion of the at-bat.

And the proof is in the pudding. Countless pitchers can sustain miniscule walk rates despite locating precious few pitches within the zone. Case in point: Hiroki Kuroda and Shaun Marcum have the third (41.9 percent) and fourth (42.3 percent) lowest zone percentages in the league, despite maintaining walk rates of 2.37 BB/9 and 2.13 BB/9, respectively. This is due to their exceptional O-Swing rates of 35.5 percent for Kuroda and 32.8 for Marcum.

Stuff and Approach

Still, despite his ability to throw balls in the zone, Daisuke himself may be his own worst enemy. Scouts and coaches has long espoused his issues with nibbling the corners of the zone — a deficiency that, no doubt, allows plenty of batters to get ahead of him and contributes to his large walk totals.

Not surprisingly, Matsuzaka has underperformed his expected walk totals in every season of his career.

  • 2010: Expected BB/9, 3.085; Actual BB/9, 4.27
  • 2009: Expected BB/9, 4.133; Actual BB/9, 4.55
  • 2008: Expected BB/9, 3.902; Actual BB/9, 5.05
  • 2007: Expected BB/9, 3.281; Actual BB/9, 3.52

And, since error margins on expected walk values seem to be an unrepeatable skill for the vast majority of Major League pitchers, there is something to be said for a pitcher who does it in four out of four seasons.

The “why” behind this trend, however, is a far more tricky to decipher, and is a subject for another post.

But, getting back to Daisuke’s 2010, his improvement in BB/9 has been the result of his improved O-Swing percentages. And, like trying to figure out why he continually walks more batters than he rightfully should, his O-Swing increases are a similar conundrum.

When it comes to stuff, at first glance, it would seem that his slider would be the logical place to look, as it is the only pitch in his repertoire that has change significantly from his 2009 offerings.

In the case of an increase in O-Swing, what we would expect to see is a change in break that would make it resemble a fastball. This would spike O-Swing because batters would chase the slider off the plate thinking that it was a fastball — increasing the number of O-Swings.

However, the opposite has happened, as this season the slider’s movement has differentiated further from the fastball, with a larger gap in both horizontal and vertical movement in 2010 than in years past. Therefore, with the new slider, it would seem that hitters would pick up the pitch’s movement earlier and lay off the pitch outside of the zone.

This suggests that a more deceptive slider is not the case.

Ruling this out, we are left to believe that Matsuzaka has altered the way in which he is setting up his pitches. Perhaps he is locating and sequencing pitches differently than in the past, or has improved his communication and chemistry with Victor Martinez. However, without reliable information other than going directly to the source, I’ll refrain from speculation on this point.

For now, we’ll assume that the increase in O-Swing is due to a change in approach. Unfortunately, we have to leave it at that.

However, the good news is that, if his 2010 success is based on a change in approach, there is reason to believe Matsuzaka can sustain his improved O-Swing percentage into 2011.

And, with the team’s commitment to Daisuke and the Seibu Lions growing to approximately $18.5 million next year, the team can only hope that Daisuke will maintain his gains.

And he’ll have to, as Boston can ill-afford another season of poor walk rates, inefficiency, and sub-par production.