Tuesday, June 12, 2012

Musings on Baseball: The Pitcher Win

Many of the serious baseball analysts I read and listen to deride the pitcher win stat, saying that it says very little about how well a pitcher actually pitched, especially since starters rarely pitch more than six innings.  There are so many other people playing the game and so many other variables that go into winning a game that giving one player credit for the win is just ridiculous.  I am in complete agreement with this assessment.  When I hear people on the radio or television saying, "So-and-so is going for his fifth consecutive win," or "Such-and-such is still looking for his first win of the season," I find myself screaming at the voices who can't hear me, "That doesn't mean anything!"  However, I think the pitcher win is here to stay.

Let's look at three statements:
(1)  Pitcher X has a win in 7 of his last 10 outings.
(2)  Pitcher X has a quality start in 7 of his last 10 outings.
(3)  Pitcher X has a Game Score of 70 or higher in 7 of his last 10 outings.

What do these three statements actually tell us about how well Pitcher X actually pitched?

In order to get a win, a pitcher must be the pitcher of record after the fifth inning.  To be the pitcher of record a pitcher must be the pitcher who was pitching when his team gained the lead for good.  So, if a team took the lead in the first inning and never surrendered it, the pitcher who pitched the fifth inning would get the win.  If a team took the lead in the eighth inning and never surrendered it, the pitcher who pitched the eighth inning would get the win.  (It's a little more nuanced and complex than that, but that's the gist of it.)  So for a starter to get a win, he has to pitch at least five innings, have a lineup behind him that scores more runs than his gives up, and have the relievers that come after him not give up the lead.

With so many variables in play, the pitcher win can be a pretty fickle stat.  Sometimes, the pitcher who pitches the worst in a game is the one who gets the win.  This happened on the first day of the season this year.  Justin Verlander pitched eight shutout innings for the Detroit Tigers.  Jose Valverde came in to pitch the ninth inning with a 2-0 lead.  He proceeded to give up two runs in the top of the ninth.  The Tigers scored a run in the bottom of the ninth to win the game, but because Valverde was now the pitcher of record, he was the pitcher awarded with the win.  But who was more deserving of the win, the pitcher who gave up 0 runs in 8 innings or the one who gave up 2 runs in 1 inning?

Also, lack of run support can lead to a pitcher not getting any wins.  In 2007, San Francisco Giants pitcher Matt Cain was one of the best pitchers in the National League.  He was among the league leaders in several pitching stats.  Except wins.  Because of the Giants' anemic bats, Matt Cain got a measly 7 wins in 2007.  In 2008 he was just as good, and even tied for the league lead in games started.  He got a whopping 8 wins.  Meanwhile, in 2007, Jamie Moyer of the Philadelphia Phillies pitched almost exactly the same number of innings as Matt Cain, yet gave up more hits and more runs than Cain while striking out fewer batters.  His win total?  14.

So statement 1 says that Pitcher X pitched at least 5 innings in those 7 games and got good run support.

In order to get a quality start, a pitcher must pitch at least 6 innings and give up fewer than 3 earned runs.  (For those of you not in the know, an earned run is a run that has been determined to be the fault of the pitcher.  Unearned runs are runs that are not the fault of the pitcher, usually scoring as a direct result of an error on the part of one of the fielders.  The idea being that a pitcher should not be penalized for the failures of his defense.)  If a starter pitches a quality start, he puts his team in a good position to win the game.  In April of this month, teams whose pitchers got a quality start had a combined .648 winning percentage.  That comes to 105 wins in a 162 game season.  To put that into perspective, the Philadelphia Phillies last year had the most wins in baseball with 102.

The big advantage of the quality start is that it completely removes run support from the equation.  And it's hard to be dissatisfied with your pitcher's performance if he gets a quality start.  However, the quality start is still imperfect.  It ignores unearned runs.  Also, if a pitcher does the bare minimum requirements for a quality start, his stats end up being pretty pedestrian.  Also, a pitcher who pitches 9 innings but gives up 4 runs does not get credit for a quality start, even though that's an overall better performance than a six inning three run start.

In 2007, Matt Cain had 22 quality starts, tied for sixth in the league.  (Jamie Moyer had 18.)  He had a quality start 69% of the time.  In 2008 he had 21 quality starts.  While they don't tell the whole story, his quality start totals are a much better indicator of his performance than his win totals.

So statement 2 says that Pitcher X pitched at least 6 innings in those 7 games and gave up no more than 3 earned runs in each one.  (Or, pitched like Matt Cain in 2007.)

Game Score is a statistic that was developed by baseball statistician Bill James.  It awards points for innings pitched and strikeouts, and subtracts points for walks, hits, and runs allowed.  Most quality starts get game scores in the upper 50s and 60s, with an average around 64.  A game in which a pitcher pitched 7 innings with 1 run, 4 hits, 1 walk, and 6 strikeouts would get a Game Score of 70.  That is a really nice outing, one that fantasy baseball players covet.  Roughly one quarter of all quality starts have a score of 70 or better.

Last year, Justin Verlander led the majors with a 65.9 average Game Score.  The first game of the season where he was brilliant but did not get the win, he scored an 84.  In 2007, Matt Cain had an average Game Score of 54.7, good for ninth in the league.  This year to date, Cliff Lee is the highest ranked pitcher in average Game Score with exactly 10 starts.  In those 10 starts he has 0 wins, 7 quality starts, and 3 games in which he got a Game Score of 70 or better.

So statement 3 says that Pitcher X pitched like an ace 7 out of the last 10 games.  And unless the other 3 games were really ugly, over his last 10 games, Pitcher X has been one of the best pitchers in baseball.

If I was to rank the three statements as to how much they actually tell us about Pitcher X's performance over his last 10 starts, I would rank them 3, 2, 1.  But if I was to rank them how they sound to a casual fan, the rankings would reverse.  Because I am guessing that only the hardcore stat-heads are even aware of or interested in Game Score and a score of 70 doesn't mean much without any context.  Quality start sounds better but unspectacular.

But when I say that Pitcher X won 7 of his last 10 starts, it sounds amazing.  It says that Pitcher X is a dominating force.  It says that when Pitcher X starts, his team has at worst a .700 winning percentage.  It says Pitcher X will carry his team to victory because Pitcher X is a Winner!  And after all, isn't it all about winning?

Which is why the pitcher win is here to stay.  No amount of number crunching will ever sound better than, "Pitcher X got a win!"


James said...

Welcome back Matt. Good to see this blog flash to life again. So... when are you going to dump some more Tolkien wisdom on us?

Herch said...

When it happens. I have a couple ideas, but none of them are clamoring to be written about yet.

Herch said...

Interesting that shortly after I write a whole post about how good of a pitcher Matt Cain really is, he goes out and pitches a perfect game. I'd like to go on record now and say that Yu Darvish, Colby Lewis, Derek Holland, and Matt Harrison are all better than their win totals show.