During last night’s Mets–Rockies broadcast, while discussing the rising strikeout and lowering walk numbers in baseball the last couple seasons, Ron Darling made the intuitive assumption that if strikeout rates are up, then swings and misses must be sky-high as well. The Mets broadcaster is right about the strikeouts – since the start of 2012, MLB hitters have struck out an all time high 19.8% of the time, up from 16.4% in 2002 and 17.5% in 2007 – but he was wrong about the latter, and a look at the numbers leads to an entirely different conclusion.
While the percentage of balls hitters have swung and miss on has been down in 2012 and 2013 – 20.3% each year, according to Fangraphs – this is really a rather nominal change from the 2004-2011 average of 19.4%. It’s not even as high as it was a decade ago, when batters posted historic levels of 21.2% and 20.6% in 2002 and 2003, respectively.
These numbers are rather startling; how can strikeout rates be so high if hitters are making either virtually the same amount or more contact than before? The answer appears to be in pitchers’ gameplans and batters’ selectivity, which could help explain the lowered walk rates – they’ve declined by over 10% since 2002 – we’ve been seeing as well.
In this pitcher’s era, hurlers have seemingly turned to living outside the strike zone for success. In 2004, 55% of all pitches were in the physical zone, and from 2002 to 2009 that number averaged out at 53%. In 2012, the rate fell to 45%, where it has remained for the duration of this season. Considering the approximate 700,000 pitches thrown per season, MLB hitters are seeing a startling 70,000 fewer strikes, i.e. hittable pitches, than they were ten years ago.
The problem is that as pitchers shift to throwing more rising fastballs above the chest and curveballs at the ankles, hitters’ eyes have apparently become less acute. In tune with the sabemetric philosophy of plate discipline, hitters have tried to become more patient, swinging at only 65% of pitches in the zone this year and last, a sharp decline from the 70% players posted in 2002. Even if the goal is to be more disciplined and increase On Base Percentage, by taking pitches in the zone, hitters are just accruing more strikes, which invariably leads to more strikeouts. Hitters aren’t striking out more because they are making contact on fewer swings, they’re striking out more because too many of those swings are coming when they are already in an 0-2 hole.
Surprisingly, while the in-zone swing percentage has decreased substantially, the overall swing rate is just about where its been for the last decade. This discrepancy is due to the fact that hitters are chasing too many pitches off the plate. The percentage of balls out of the zone swung at has almost doubled since 2004, when it rested at a decade low 16.6%. Just look at Matt Harvey and his devastating slider. He only throws the pitch over the plate 38% of the time, but batters have still swung at half of the 439 sliders he’s thrown this year, leading to Harvey’s amazing season and Cy Young candidacy.
This would explain why walks have dropped off to such a degree in the last couple seasons – its awfully hard to draw base on balls when hitters are taking called strikes and fishing at bad pitches out of the zone. Its also one of the primary contributors to 2013′s slightly deflated contact rates as it is obviously much more difficult to make contact on pitches a foot off the plate then ones right down the pipe.
For the era of pitching to end, position players are simply going to have to live up to the two main sabemetric tenets – walk more, strikeout less. To do so, they won’t have to be better, just smarter and more disciplined.