Improving the Phillies’ pitching staff for 2018: What is a “good pitcher”?

Ethan Witte recently wrote about whether Ben Lively was good or not. I wasn’t entirely sure what it means to be “good” in the context of the re-inflated pitching environment of 2017. In another post, the commentariat discussed the historic performance by the 2011 Phillies staff - a performance that I thought we’d be unlikely to see again even from the same pitchers if we could bring them here in a time machine. The game has changed.

I spent some time at Fangraphs looking back at the years from 2007 through 2017, inclusive. Well? What did I learn?

The gimp who lives in my basement

This chart represents pitching statistics for “the league” for each year from 2007 through 2017, inclusive. Each year is subdivided into pre-ASB and post-ASB using Fangraphs’ splits. I did not break it out into relievers versus starters.

I highlighted highs and lows using the boxes and colored cells. I did this by hand, and may you all forgive me if I blew it in missing the “high” and “low” numbers in each category. I neglected to highlight the “low” (2014-2H) and “high” xFIP (2007-1H) numbers. I tried hard. I did. Take a sharpie and write on your screen if it bugs you that much.

A league-average pitcher in the first half (non-”Hittin’ Season") of 2007 had an xFIP of 4.49. In the second half (YTD) of 2017, that xFIP is now at 4.39. So...everything is pretty much the same, right?

Obviously not. Much has been written about the evolution of baseball, including the rise of the strikeout. I’m not going to belabor that or re-plow that field. And honestly, the main reason I’m writing about this tonight is not because the idea that pitching has changed is novel, but just to frame the debate that’s coming up during the off season about how to make the starting rotation and bullpen better.

We need to know what is “good” in the current environment by knowing what the environment is and aiming for something better.

The most striking numbers to me were the following:

1. Strikeouts.

I said wasn’t going to re-plow the field, but the numbers marched steadily higher every year since 2007. The consistency of the increase is pretty remarkable. Other than 2010 to 2011, the strikeouts per 9 innings went up year over year every single year.

Another remarkable feature is that post-ASB strikeout numbers per nine innings are higher every year compared to the pre-ASB strikeout numbers. Hittin’ season is also apparently strikeout season. I thought that was kind of interesting.

2. Walks.

In 2014, walks bottomed out. My sense is that there was a pretty clear focus on reducing walks from 2007 through 2014 as the conventional analytical wisdom about walks was implemented on the field. This maxed out in 2014 when MLB reached “peak modern dead ball” with a collapse in xFIP to 3.70 in the second half of 2014, which was .79 below the number for the first half of 2007. Offense had dropped by about 20% over seven years as walks dropped, strikeouts rose, and homers fell.

Then, all of a sudden, walks started to increase in 2015. Why? Did pitchers suddenly stop care about putting people on base? Probably not.

3. Ground balls.

The ground ball percentage number bounces around some, but there are broad trends. In 2007, it was in the low to mid 43% range. It increased to a peak of low to mid 45% in 2015. It pretty consistently rose, as teams likely prioritized ground ball pitchers, realizing that grounders don’t result in many extra-base hits, including home runs since, famously, they can’t go over the fence.

Since 2015, the ground balls have dropped almost all the way back to 2007 numbers in just two years. Why? Again, it is unlikely that pitchers no longer care about generating ground balls.

4. Home runs.

Homers bounced around between 0.90 and 1.10 per game from 2007 through 2013 with the exception of a single half season. Most of the xFIP reduction during that period appears to have resulted from increased ground balls, increased strikeouts, and decreased walks. Homers varied, but did not have any clear consistent direction, year to year.

In 2014, homers fell off the face of the earth, breaking below 0.90 for both halves of the season and in the climax of a three year mini-trend. As all pitching inputs “peaked” on the side of pitchers (walks down, ground balls up, and strikeouts up), homers flatlined and offense died.

The following season, particularly in the second half of 2015, homers per game hit 1.09, which was a level not seen in the 17 prior half seasons. Did all the pitchers in the majors collectively just start to suck? Did Daniel Murphys all over MLB suddenly start to rake? I guess it is possible.

If the 2015 scoregasm was an aberration, 2016 was an uberration. Homer rates exploded **again**, with pre-ASB and post-ASB numbers far exceeding anything seen in the prior ten years. This despite the fact that strikeouts continued to rise and ground balls were still relatively high for the period in question. Walks began to rise, though, which is not surprising given the 25-30% increase in homers per game from 2014’s nadir through 2016.

Since 2017 started, the homerfest jumped up another 10% on the newly increased base established the prior year to a number very close to 1.3 homers a game. Again, has anything really changed about the game in that time frame? There’s been no expansion, PED testing is as tough as it has ever been, parks are all pretty much the same (though some have adjusted fences), and pitchers continue to improve their strikeout numbers. I wonder whatever it could be?

Regardless of whether the ball is juiced, the profusion of offense has altered the baseline of what a “good” pitcher is compared to what we saw in MLB just two or three years ago.

An xFIP of 4.40 in 2014 was dreck. A 2017 pitcher with an xFIP of 4.40 is an average pitcher. Starters in 2017 (YTD) have an xFIP of 4.43 in MLB and 4.33 in just the National League. The Phillies need some starters of that caliber or better. The 2017 versions of Jaime Garcia and Justin Verlander are in that performance range, to give some examples.

I’m not advocating for any particular pitcher. I’m certainly not advocating for Verlander or Garcia. I just wanted to help frame the debate for the off season by reminding all of us that the universe of MLB has moved xFIP up by 0.50. When we look to evaluate the in-house options controlled by the Phillies, it will be helpful to remember that.

With all that said, what would you do to solve 2017’s problem of poor starting pitching for the 2018 Phillies? Also feel free to discusss whether it perhaps could be a significantly lower barometric pressure across the entire United States from April to September that is causing all these homers. I mean, that’s probably it. Occam’s Low-Pressure System and all.