Does Rick Porcello Finally Have a Strikeout Pitch?

After seeing ace Justin Verlander allow eight runs in less than three innings to the powerful Texas Rangers on Thursday, Tigers fans feared the worst when Rick Porcello took the mound last night.  Porcello silenced doubters with a strong performance against a tough line-up allowing just one run while striking out six in 5 2/3 innings.  This was Porcello's fourth solid game since his first-inning meltdown versus the Angels on April 20.  During that span, he has a 3.24 ERA and 24/5 K/BB ratio over 25 innings. 

The most encouraging feature of the above statistical line is the high strikeout total.  According to Porcello's game logs on Baseball-Reference.com, he has struck out six plus batters in his last three games.  This is hardly an impressive feat on a staff which features strikeout artists such as Anibal Sanchez, Max Scherzer and Verlander.  However, it is the first such three-game string of Porcello's career. 

I wanted to see which pitches the strikeouts came on, so I checked the Game Day results of his last three games at MLB.COM.  THey were as follows:

May 2 versus Houston
Change-up swinging
Change-up swinging
four-seam fastball called
Change-up called
Curveball called
Change-up swinging
Four-seam fastball swinging

May 12 versus Cleveland
Change-up swinging
Sinker called
Sinker called
Sinker swinging
Change-up called
Four-seam fastball called

May 17 versus Texas
Four-seam swinging
Change-up swinging
Change-up swinging
Change-up swinging
Curveball swinging
Curveball called

If you count them up, you'll see the following totals:

Change-ups 9
Four-seam fastballs 4
Sinkers 3
Curves 3

So, he is making good use his change-up which is something that Jeff Roberts of Eye on the Tigers noted earlier this week. Roberts used FanGraphs data to show that it has been Porcello's most improved pitch this year in terms of linear weights results.

Porcello has had good stretches before where he prevented runs with good control and lots of ground balls, but his inability to miss bats (only five strikeouts per nine innings for his career) has always come back to haunt him.  His annual  strikeouts by pitch according to Brooks Baseball.net (plus last night's game) are shown in the table below.  (You may notice that the strikeout totals in the bottom row are not quite right in some cases, but I trust that the Brooks Baseball pitch type data are the most accurate available. 

Table 1: Rick Porcello's Strikeouts by Pitch Type

Pitch type	2009	2010	2011	2012	2013
Four-seam fastball	25	22	24	17	3
Sinker	33	30	36	55	7
Slider	11	23	37	17	4
Curveball	7	1	5	4	4
Change-up	12	10	14	14	13
Totals	88	86	118	107	27

Data source: Brooks Baseball.net

The most striking number on the table is the 13 strikeouts on change-ups already in 2013, nine of which came in the last three games.  This is remarkable because Porcello has never struck out more than 14 on his change in any season.  Some of that is due to increased usage of the pitch which is a good thing if it's working.  Time will tell whether he can maintain the effectiveness of his change throughout a full season, but it's encouraging and something to watch in his upcoming starts.

Verlander's Worst Game Ever?

Tonight's pitching duel between aces Yu Darvish and Justin Velander did not live up to its' advance billing as Darvish was mediocre and Verlander was awful.  So, instead of admiring a masterpiece, Tigers fan discussed on Twitter whether this was Verlander's worst game ever.   Everybody had their own opinion on Verlander's worst game, but this game was certainly among them. 

One way to measure the strength of a game by a pitcher is by Bill James' Game Score metric.  It is computed as follows:

• Start at 50 points.

• Add one point for each out recorded.

• Add two for each inning pitched after the fourth.

• Add one for each strikeout.

• Subtract two for each hit.

• Subtract four for each earned run.

• Subtract two for each unearned run.

• Subtract one for each walk

Prior to today's game, Verlander's 2013 game scores ranged from 43 to 80 with an average of 62.  Today, he allowed 8 runs on 6 hits and 2 walks in just 2 2/3 innings and ended with a Game Score of 15.  According to Baseball-Reference, that was tied for his worst game score ever.  The others are listed in Table 1 below.

Table 1: Justin Verlander's Worst Game Scores Ever

Date	Opponent	IP	H	R	ER	BB	K	GS
04/13/2006	CLE	2 1/3	7	7	7	1	0	15
09/01/2008	NYY	1 2/3	7	8	5	2	2	15
04/06/2009	@ TOR	3 2/3	8	8	8	2	4	15
05/16/2013	@TEX	2 2/3	6	8	8	2	3	15

Data source: Baseball-Reference

Verlander's worst games ever included seven runs in 2 1/3 innings versus the Indians during his rookie year in 2006.  He failed to get though two innings allowing 8 runs (5 earned) against the Yankees in September, 2008.  He also allowed 8 runs in 3 2/3 innings on opening day in Toronto in 2009.

Verlander was just as bad tonight, but it could have been worse.  Tigers right hander Scott Sanders once had a game score of -15 (Negative 15) in a game in 1998 where he gave up 11 runs on 16 hits in 4 innings. 

Anibal Sanchez Among Early Pitching Leaders

Today, I'll take my first look at some of my favorite sabermetrics pitching leaders.  Most readers of this blog are aware of the limitations of ERA in evaluating pitcher performance.  Two of the biggest issues are:

• ERA gives pitchers full credit/blame for results of batted balls in play despite the fact that they share that responsibility with fielders.  For example, a pitcher with a strong defense behind him will tend to give up fewer hits (and thus fewer runs) than if he has a poor defense behind him.

• ERA gives pitchers full responsibility for sequencing or timing of events, that is, it assumes that they can control when they give up hits and walks. For example, if a pitcher pitches extraordinarily well with runners in scoring position in a given year, he will have a lower ERA than if he had a typical year in those situations. Additionally, a pitcher who tends to bunch base runners together in single innings will have a higher ERA than if he had a typical year distributing base runners more evenly.

In reality, pitchers have limited control over both the number of batted balls that drop for hits and sequencing of events.  Thus, Defense Independent Pitching Statistics (DIPS) such as FIP, xFIP, tERA and SIERA have been developed to remove some of the noise of ERA.  DIPS are based on things that pitchers do control for the most part - walks, hit batsmen, strikeouts, home runs and types of batted balls (ground balls , fly balls, line drives, pop flies).

Because they are based on things that pitchers essentially control, the DIPS metrics are said to be better measures of true talent than ERA.  As a result, they are also better than ERA at predicting future performance. However, they only measure a portion of a pitcher's talent and should be used as complements to ERA rather than as replacements. 

It is not known exactly how much control pitchers have on the results of balls in play, but recent research tells us that some pitchers are better than others at preventing hits on balls in play.  For example, Mike Fast, formerly of Baseball Prospectus and now a MLB sabermetrician, used Sportsvision's hit f/x data to show how pitchers varied on the speed of balls off the bat.

So, rather than making the big leap from ERA to FIP, it might be a good idea meet half way.   Instead of removing hit prevention and sequencing in one step, it might be better to remove one factor at a time.  Bill James did that with his Component ERA (ERC).  Applying the runs created methodology to pitchers, he determined what a pitcher's ERA should have been based on walks, hit batsmen,  strikeouts, homers AND hits allowed.  I'm going to look at some similar statistics here based on more modern measures such as linear weights and Base Runs. 

We often use Weighted On-Base Average (wOBA) to measure overall hitting performance and it can also be used for pitchers.  The American League wOBA Against (wOBAA) leaders are shown in Table 1 below.  Hishashi Iwakuma of the Mariners currently leads the league with a .208 wOBAA.  The top Tiger is Anibal Sanchez, sixth in the AL at .251. Max Scherzer was 11th prior at .267 prior to today, but likely dropped down the list quite a bit with today's performance.  Justin Verlander (.267) and  Doug Fister  (.287) are 12th and 18th respectively.

Table 1: AL wOBA Against Leaders

Player	Team	G	IP	wOBAA
Hisashi Iwakuma	SEA	8	51.2	.208
Yu Darvish	TEX	8	52.2	.240
Clay Buchholz	BOS	8	58.2	.244
Felix Hernandez	SEA	9	64.2	.246
James Shields	KCR	8	58.0	.247
Anibal Sanchez	DET	8	52.2	.251
Jon Lester*	BOS	8	52.2	.252
Chris Sale*	CHW	8	56.1	.258
Hiroki Kuroda	NYY	8	50.2	.259
Derek Holland*	TEX	8	55.1	.261
Max Scherzer	DET	7	47.1	.267
Justin Verlander	DET	8	51.1	.268
Matt Moore*	TBR	8	48.0	.275
Justin Masterson	CLE	9	63.0	.277
Ervin Santana	KCR	7	48.1	.284
Jake Peavy	CHW	7	45.2	.285
Doug Fister	DET	8	50.0	.287
Zach McAllister	CLE	7	43.2	.291
Wei-Yin Chen*	BAL	8	47.1	.292
A.J. Griffin	OAK	8	51.2	.300

Data source: Baseball-Reference

It's generally a good to convert to runs allowed when trying to evaluate pitchers, so I'll do that next.  The Base Runs measure was created by David Smythe in the early 1990s.  It is based on the idea that we can estimate team runs scored if we know the number of base runners, total bases, home runs and the typical score rate (the score rate is the percentage of base runners that score on average).  Base Runs also works well for individual pitchers.  The complete formula can be found here.

Sanchez has 16 Base Runs Against in 52 2/3 innings so far this year.  This means that he should have allowed an estimated 16 runs based on the number of base runners, total bases and home runs he has allowed.  He has allowed 14 actual runs, so runs are scoring against him at a slightly lower rate than you would expect so far.  That could possibly be due to good defense, unfortunate timing or just bad luck on locations of batted balls.

Sanchez has 10 Base Runs Above Average (RAA) which means that he has saved the Tigers an estimated 10 runs compared to the average pitcher in the same number of innings.  Table 2 shows that he is ninth in the league on that metric.  Iwakuma is the league leader at 14.   Other Tigers among the leaders include Verlander and Fister, both with 8.      

Table 2: AL Runs Saved Leaders

Player	Team	G	IP	Base Runs	RAA
Hisashi Iwakuma	SEA	8	51.2	11	14
Clay Buchholz	BOS	8	58.2	15	13
Felix Hernandez	SEA	9	64.2	18	13
James Shields	KCR	8	58.0	16	13
Yu Darvish	TEX	8	52.2	14	11
Chris Sale*	CHW	8	56.1	17	10
Justin Masterson	CLE	9	63.0	21	10
Jon Lester*	BOS	8	52.2	15	10
Anibal Sanchez	DET	8	52.2	16	10
Derek Holland*	TEX	8	55.1	18	9
Hiroki Kuroda	NYY	8	50.2	15	9
Justin Verlander	DET	8	51.1	17	8
Doug Fister	DET	8	50.0	17	8
Max Scherzer	DET	7	47.1	16	7
Wei-Yin Chen*	BAL	8	47.1	18	5

Data source: Baseball-Reference 

Finally, Table 3 shows that Sanchez has allowed 2.69 Base Runs per nine innings.  About 93% of runs are earned, so multiply this result by .93. to put it on the same scale as ERA. The final result is a weighted component ERA.  Although, I am not using linear weights here, I call it WERC because others have said they like the name. It's really not a novel idea though.  Patriot of Walk Like a Saber has been using Base Runs to evaluate pitchers for a while but prefers to not convert to the ERA scale.

Getting back to the example, Sanchez has a 2.50 WERC which places him seventh in the league. Once again, Iwakuma (1.85) is the AL leader.

Table 3: AL WERC Leaders

Player	Team	G	IP	Base Runs/9 IP	WERC
Hisashi Iwakuma	SEA	8	51.2	1.99	1.85
Clay Buchholz	BOS	8	58.2	2.33	2.17
James Shields	KCR	8	58.0	2.42	2.25
Yu Darvish	TEX	8	52.2	2.43	2.26
Felix Hernandez	SEA	9	64.2	2.55	2.37
Jon Lester*	BOS	8	52.2	2.65	2.47
Anibal Sanchez	DET	8	52.2	2.69	2.50
Chris Sale*	CHW	8	56.1	2.72	2.53
Hiroki Kuroda	NYY	8	50.2	2.76	2.57
Derek Holland*	TEX	8	55.1	2.89	2.69
Justin Masterson	CLE	9	63.0	2.93	2.73
Justin Verlander	DET	8	51.1	2.96	2.75
Max Scherzer	DET	7	47.1	2.96	2.76
Doug Fister	DET	8	50.0	3.03	2.82
Wei-Yin Chen*	BAL	8	47.1	3.35	3.12

 Data source: Baseball-Reference

Some may have noticed that the Tigers rank lower on WERC than FIP which had their big four starters - Sanchez, Verlander, Scherzer and Fister - all in the top eight entering today.  The FIP metric, of course does not involve hits allowed.  The Tigers starters have been allowing a lot of hits on balls in play as all four have BABIPs of .312 or greater.  You could blame this on poor fielding or bad luck, but we don't know to what extent that's true.  Therefore, it's useful to see where they stand if hits are taken into account.  

I would guess that the Tigers FIPs and WERCs will move closer together as the season progresses.  I'll update these numbers again when we have a larger sample size.