Photo courtesy Richmond Times-Dispatch

In his first eight starts of the 2012 season, Senators pitcher Danny Rosenbaum looked superhuman on the mound as he mowed down the opposition methodically to run his record to 5-0. Since then though, Rosenbaum has appeared, dare I say, average. 

He has had seven straight starts that have not come close to the kind of performance he put on from April through mid-May. Ask him or pitching coach Paul Menhart and I’m sure both will talk about issues with command and location.

We delved into the numbers to try and understand Rosenbaum’s season through a breakdown of some key statistics. For the sake of our post, we’ll separate his season into two periods:

Superman (April 8 – May 17): 57.2 IP, 36 H, 6 BB, 37 K, 4 ER, 0.62 ERA, 0.73 WHIP
Clark Kent (May 23 – June 24): 40.1 IP, 55 H, 13 BB, 25 K, 26 R, 5.80 ERA, 1.69 WHIP

1. Thanks, Captain Obvious!

OBA: .176 (Superman) vs .333 (Clark Kent)
OBP: .199 (Superman) vs .382 (Clark Kent)

The first and most obvious point is that opposing batters are hitting and walking more. And when I say more, I mean almost to the point of doubling their productivity at the plate.

No one expected Rosenbaum to continue posting the absurd numbers he did during the Superman period. Unless your name is Pedro Martinez in 1999-2000 or Ron Guidry in 1978, it was only a matter of time until his numbers came back to something more “normal”. But no one expected the wheels to come off as drastically and quickly as they have.

2. Play with Fire and Eventually You’ll Get Burned

OBP (Superman): .276 (leading off) vs .170 (other)
OBP (Clark Kent): .442 (leading off) vs .363 (other)

Even during Rosenbaum’s Superman period, batters leading off innings got on base at an alarmingly high rate compared to other batters in the order. That difference continued at roughly the same rate during the Clark Kent period, but just the fact that leadoff hitters have gotten on base in 19 of the 43 innings Rosenbaum has started since May 23rd is disconcerting and troubling.

Keep in mind that this specific statistic is not a guaranteed precursor to success or failure as you’ll notice in both games Rosenbaum pitched against the Binghamton Mets this season. In one of the games, four of the nine leadoff batters reached base and in the other game, only one of the seven managed the feat. As you can probably already guess, the former example was a 2-1 complete game victory for Rosenbaum and the latter was a 4-1 loss.

3. FedEx Air & Ground

GO/FO rate: 5.65 (Superman) vs 4.07 (Clark Kent)

Rosenbaum still induces a large number of groundball outs, but his ratio to flyball outs has plummeted 28% during the Clark Kent period. With increased runners on base (especially leading off an inning), this drop adversely affects double-play opportunities and the ability to hold runners to station-to-station baseball.

For the last two points, I’ll introduce a stat I’ll call Count at Outcome, or CaO. This reflects the actual, final count when an outcome (i.e. hit, walk, out, etc) occurred and not for all counts during an at-bat.

4. Work Ahead of the Batters, Part I

OBA (CaO: 0-1, 0-2, 1-2): .092 (Superman) vs .267 (Clark Kent)

To say that Rosenbaum was dominant during his Superman period when he got ahead in the count is an understatement. Holding opponents to a .092 batting average regardless of the count was off the charts and a natural regression to the mean should have been expected. But to now have batters hitting at a .267 clip when they are down in the count is way too high and shows something is amiss.

5. Work Ahead of the Batters, Part II

OBA (CaO: 1-0, 2-0, 3-0, 2-1, 3-1, 3-2): .289 (Superman) vs. .558 (Clark Kent)
OBP (CaO: 1-0, 2-0, 3-0, 2-1, 3-1, 3-2): .373 (Superman) vs. .661 (Clark Kent)

Pitchers are taught to work ahead for a reason. When behind in the count, bad things tend to happen because a batter can sit on a certain pitch or location and put a much better swing on it then when he’s trying to protect or guessing. Therefore, it’s no surprise to see that even during his Superman period, opposing batters were hitting .289 and getting on base at a .373 clip when he was behind in the count. That should be expected.

But during his Clark Kent period, Rosenbaum has been absolutely putrid when working from behind. To put how bad into very simple math, two out of every three batters reach base safely when they are ahead in the count. For a pitcher like Rosenbaum who relies on painting corners, those kinds of numbers make it tough and almost impossible to succeed,

Tonight, Rosenbaum takes the mound at Metro Bank Park for his scheduled start against the Altoona Curve. Here’s hoping he regains the form that he had for his first eight starts and we get to see Superman once again.