If the question is where Johan Santana goes from here, the answer is that we don’t know. But we can expect that he’s probably not going to be the guy he used to be for the Twins.

One of the problems is that our ability to figure out where Santana’s going is compromised because a lot of noise gets in the way of finding out how good he really is now. No pitcher performs in laboratory conditions but he has had more than his fair share of challenges lately:

- off-season surgery

- reports of a blister

- a mechanical problem (“catapulting”)

- three managers in three years

- three pitching coaches in three years

- three home parks in three years

- change of leagues

- change from a stable organization to the Mets madhouse

We don’t know how or if those factors have diminished Santana’s ability to pitch. Some of them, like changing leagues and his new home park, have probably even helped him.

We also need to keep in mind that we’re looking at a snapshot, even though it’s already August: there is still a third of the season left to play. Last year at the All-Star Break he seemed to be in the same spot he’s in now but then went 8-0 in the second half with monthly ERAs of 2.65, 1.91, and 1.83. He’s rallying this year, too. In July Santana has posted game scores of 64, 71, 70, 30, and 76. In his most recent start he broke out his strikeout slump by racking up 7 swinging strikeouts in 7 innings, 8 strikeouts total. We don’t want to go so far as to talk about Santana being a second-half pitcher, as if that’s a skill, but his career split shows a strong tendency to pitch better after the All-Star Break:

W%              ERA              OPS

1H      .598             3.43             .675

2H      .769             2.68             .611

It’s still early and a strong finish wouldn’t be a surprise, but, even with Santana on a roll, it’s not too early to concede that the 2009 Santana hasn’t been the Santana of old. In fact, the Santana of the past three seasons isn’t the Santana of old. He has changed, but how much has he changed and is he getting worse?

There have been some good narrow-slice analyses of Santana’s pitch data, but I want to keep this simple. To get a broader view of how his output has changed over time, I want to look at three areas of performance: some basic ratios (strikeout, walk, and groundball/flyball); his game scores; and his inning analysis. In some areas there has been a decline over the past few years, but the overall picture suggests that the Santana of 2007-2009 is holding steady. He’s not the pitcher he was in his 2004-2006 peak, but he’s not showing signs of ongoing deterioration.

RATIOS

Santana’s strikeout rate has been a mixed bag this year. His 2009 strikeout rate is up a tick from last year, but that’s on the strength of his first few starts. His SO rate has dropped significantly since then:

April 12.1

May 11.3

June 4.5

July 6.2

It’s trending back up, largely on the strength of his 8-strikeout performance last week. It’s probably too soon to draw any conclusions from the strikeout rate one way or the other.

The walk rate is another story. For the year his walk rate is up, his worst since 2002. It has been trending upward for four consecutive seasons.

His SO/BB rate is also up, its worst since 2002.

His GB/FB ratio is way down this year, from last year and his career norm. His career norm is .61. Since 2004 (left to right):

.69, .66, .69, .62, .73, .52

GAME SCORES

If we look at Santana’s effectiveness in general, and not just his ratios, we see his game scores are still well above average but they’re lower than they were in his peak years:

65, 63, 62, 59, 60, 57

If you we set the cut-off for a good game score at 60, his percentage of starts with a good game score is down from his peak years but not as much as we might have expected:

68, 70, 62, 42, 56, 62

But if we set the bar at 75 for a great game score, we see a steep drop in his number of truly dominant games. Here is the percentage of dominant starts since 2004:

38, 30, 21, 15, 12, 14

He’s not as dominant as he was from 2004-2006, but he’s throwing as many good games this season as he has the past couple of years.

PITCH TYPE ANALYSIS

Santana’s percentage of shutout innings since 2004 has remained steady:

83, 80, 80, 75, 81, 80

But his percentage of 1-2-3 innings has been trending downward:

48, 50, 46, 42, 36, 34

His percentage of “short” (10-pitch) innings isn’t showing a trend but it’s down this year:

16, 26, 22, 21, 23, 19

His percentage of “long” (20-pitch) innings shows a difference after 2006 but it’s actually down this year from the past two seasons:

14, 14, 15, 20, 21, 18

The percentage of 1-2-3 and short innings is actually more telling than it looks, if we keep in mind that for the past two seasons he has been facing pitchers twice a game.

Putting all together, the basic data shows that we’re seeing a different pitcher. Not a significantly worse pitcher, but definitely not the same guy who was winning the Cy Young Award, a point made clearly enough by his Win Shares totals. The question isn’t whether he’s a 25 Win Shares pitcher anymore, but 20.

I mentioned a lot of things that have nothing to do with his approach to pitching. But in addition to the possible influences mentioned above – injuries, mechanics, environment – one tangible thing we know has changed is his repertoire:

What has become more apparent over time is that he’s pitching to contact more often. Borrowing data from www.fangraphs.com here’s what we see:  

*O-contact%: Percentage of contact batters make on pitches outside the strike zone.

*Zone%: Percentage of pitches in the strike zone.

*Z-Miss%: Percentage of swing-and-miss pitches in the strike zone

So Santana is essentially throwing the same number of pitches in and out of the zone, but batters are making more contact on both. The swing-and-miss percentage is misleading: just like his 1-2-3 percentage, it’s trending downward even though he’s facing pitchers instead of DHs.

We don’t know if the slump he went through earlier this year was a warning sign or a fluke. If nothing else, it drove the point home that if we’re expecting a return to glory, we need to adjust our expectations. If all we get is what we’re seeing now, we’re still looking at a very good pitcher.