Thursday, December 26, 2013

Scott Diamond and ground balls

Scott Diamond had a difficult 2013.
The 2014 Bill James Handbook contains a nine-page essay by the sabermetric pioneer that digs into the "Pitcher Analysis" data. This is the segment, referred to frequently in recent weeks during posts about Ricky Nolasco and Phil Hughes, that records, pitcher by pitcher, how many strikes, how many balls, how many ground balls he got, how many swinging strikes, yada yada yada.

As one with a perhaps irrational belief in Scott Diamond — a belief that is probably a big part of my discontent with the re-signing of Mike Pelfrey, who may well keep Diamond out of the rotation —  the third part of the essay really caught my eye:

3. How important is Ground Ball Rate to success as a pitcher?

It isn't. At all.

James being James, he defends this assertion for a couple of pages. I'm not going to quote the whole thing, but his interpretation of the data makes sense. And in 2013, at least, the two groups of pitchers who had the lowest ground ball rates were the two most effective groups.

James' basic point: It's more important for a pitcher to get strikeouts than ground balls.

I believe that to be true. Yet I also believe that a ground ball pitcher — an extreme ground ball pitcher — can be effective.

Diamond was that extreme ground ball pitcher in 2012. He wasn't in 2013.

According to the Handbook: Diamond, in 2013, faced 576 batters. He got 227 ground balls (39.4 percent), 154 fly balls (26.7 percent) and 103 line drives (17.8 percent).  This appears to be on the high end of ground ball rates — the chart only gives bulk numbers — and it didn't result in a good season for Diamond.

In 2012, Diamond had 714 BF,  311 GB (43.5 percent), 149 FB (20.1 percent), 122 LD (17.1 percent). The difference is obvious. Fly ball rates up sharply, ground ball rates down sharply, line drive rate up a bit. 

What's more troublesome for the lefty: he threw just 62 percent strikes (not real high) in 2013 and had just 10 percent swinging strikes (extremely low). 

The 2013 Handbook doesn't give the same data for the 2012 season, so I can't directly compare Diamond's strike-throwing from year to year. But given the rise in his walk rate and the decline in his strikeout rate, it's a safe bet that he wasn't throwing strikes at the same rate in 2013.

None of this is really new information, of course. Diamond's 2012 success was based on doing the things he does well — throw strikes, get ground balls — extremely well, top-of-the-league well. In 2013, he declined in those things, and that won't work for him.

He doesn't have a swing-and-miss pitch. He has to work around that, and James' essay, without ever mentioning Diamond, tells us why that's not easily done.

1 comment:

  1. ( says Diamond threw 65% strikes in 2012 with 11% on swing and misses, so better, but not hugely better .