Down on the Farm: Daniel Rosenbaum, Ace of the Harrisburg Senators


The transformation of the organization’s pitching quality from abysmal to excellent is one of the best things Mike Rizzo has done as Nationals’ General Manager (technically Vice-President of Baseball Operations). At every level of the Washington system, good pitchers abound.

One of the best arms in the minor leagues belongs to Harrisburg Senator Daniel Rosenbaum. The 24-year old left-hander has excelled at every level so far on the Gulf Coast Nationals (2009), Hagerstown Suns (2010), Potomac Nationals (2010-11) and, now, Harrisburg (2011-12).

You can see Rosenbaum’s profile on the Senators’ official web site here.

Selected in the 22nd round of the 2009 player draft, Rosenbaum, from Loveland, Ohio has defied expectations that he would simply be an “organization player.” While his 88 MPH fastball makes him more of a finesse pitcher than one of Rizzo’s coveted power arms, Rosenbaum boasts a strong variety of pitches, including a cutter, slider, and excellent change-up. He has hit 92 on the radar gun at times, but location and savvy are his key strengths.

While tagged as a pitch to contact type, Rosenbaum has an above average strikeout rate (7.3 according to and a great K/BB ratio (2.98). His WHIP (walks plus hits divided by innings pitched) is an elite 1.110.

None of the above statistics are flukes of small sample size. Rosenbaum has pitched 374 innings in the bushes, with a 20-14 record and 2.29 ERA. He also keeps the ball in the park, allowing a paltry 13 homeruns.

So far this season, Rosenbaum has been better than ever. In three starts, he is 2-0, with a 1.25 ERA in 21.2 innings pitched and a complete game shutout. He has fanned 16. Better yet, Rosenbaum has not walked a single batter. If he continues to dominate at the AA level for another 10 starts, expect a promotion to AAA Syracuse.

Rosenbaum is good, but may not have a future with the Nationals since Rizzo prefers power arms. Even so, lots of teams will covet a pitcher with Rosenbaum’s ability and moxie, just like the A’s wanted a similar pitcher, Tom Milone. If the Nats are in contention at the trading deadline this year, don’t be shocked if Rosenbaum is included in a trade.

Prospects for making the Nationals in the future: Excellent, if he is not traded. Lefties with his ERA and K/BB ratio are hard to find.

Prospects for a September call-up: Excellent as well, if he is not traded, but more as another left-handed arm in the bullpen than as a starter, except in a spot situation such as the first or second game of a doubleheader.