Follow @Nationals on Twitter | Like the Nationals on Facebook

With the recent promotion of both Bryce Harper and Tyler Moore, we have had to shelve our Down on the Farm pieces we were planning to roll out in April. We listened to your calls for a report on Destin Hood. In fact, we took them seriously enough that we decided to put it into print, and will have it for you in the next edition of Nationals Magazine, available in-park for all June and July home games. But we’ve also been sitting on another particular prospect watch piece for a couple of weeks. That turned out to be fortuitous timing for us, as the man in question – left-handed starter Danny Rosenbaum – has gone out in the meantime and proven exactly why he should be featured in this space, and why you should read all about him below.

Currently heading up the rotation at Double-A Harrisburg, Rosenbaum was pointed out to us by Director of Minor League Operations Mark Scialabba back in Spring Training. If the southpaw was under the radar before the season started, this former 22^nd-round pick out of Xavier need not worry about that for long. Blessed with a low-90s fastball that he can both cut and sink, a curveball and a developing changeup, he has succeeded at every level of the system so far, and is opening eyes and making headlines in 2012.

Rosenbaum (front right) jogs with fellow pitching prospect Alex Meyer (front left) and others in Viera this spring.

Rosenbaum has quietly posted impressive numbers at every stop so far in the Minor Leagues. However, he’ll have a hard time staying a secret for much longer with the tear he’s on right now in the Eastern League. Following another sparkling start on Monday – in which he struck out five without a walk, allowing six hits over 7.0 scoreless frames – Rosenbaum’s 2012 numbers are bordering on the absurd. His ERA stands at 0.76 (3 ER/35.2 IP) and he has struck out 23 against just two walks. He leads his circuit in ERA, innings pitched and WHIP (0.70), and is currently in the midst of a 24.2-inning scoreless streak that stretches all the way back to April 13. Opponents had hit just .232 against the lefty in his career before this season; in 2012, they are batting just .180.

Since beginning his professional career with the Gulf Coast Nationals Rookie League team in 2009, the lefty has posted a sub-2.50 ERA at each stop along his path through the minors. He has been remarkably consistent along the way as well, carrying a BB/9 of around 2.5 and a K/9 above 7.0 at every level. Never a high strikeout pitcher, his strong K/BB ratio and a very low home run rate (just 13 allowed over 388.0 innings in his career) have allowed him to continue to succeed.

“Danny’s kind of a later round draft pick who came in here and put up numbers right away,” said Nationals Director of Player Development Doug Harris. “He had a chance to advance and he’s been challenged with his progression.”

Rated just 23^rd in Baseball America’s preseason organizational rankings and sixth among left-handed pitchers (those numbers coming before four of those above him, including fellow southpaw Tom Milone, were traded to Oakland in the Gio Gonzalez deal), Rosenbaum has clearly exceeded outside expectations. But Scialabba suggests he may even be better than Milone, who is off to an excellent start out in Oakland.

“He compares with Milone physically,” said Scialabba. “But I think his stuff might even be a little better.”

In referencing a prospect, it always helps to try to make such comparisons, in order to help project the type of player he might become as he fully develops. When you are Jewish and left-handed, of which Rosenbaum is both, Sandy Koufax references are inevitable. There has been a deeper connection to the Dodger great than just that in Rosenbaum’s life, though, as he explains.

“Growing up you always heard about Sandy Koufax, who played at the University of Cincinnati,” he said, referencing the school the cross-town rival just a few miles down the road from Xavier. “People were always saying ‘Oh, there’s the next Sandy Koufax.’ It’s a real privilege to even be considered in the same sentence.”

Rosenbaum has been nearly perfect for Double-A Harrisburg this season. (Will Bentzel/Harrisburg Senators)

A better recent comparison for Rosenbaum on the field might be Ted Lilly, a similarly-sized lefty with a strong cutter/curveball/changeup repertoire. Rosenbaum has actually posted better Minor League numbers in nearly every statistical category (save for strikeouts) than Lilly, who was twice an All-Star and posted double-digit win totals in nine consecutive Major League seasons. Lilly was a fairly low profile, 23^rd-round pick by the Dodgers, but earned his way to the Major Leagues through his competitive, workman-like approach on the mound. While Rosenbaum was disappointed on draft day, he hopes to follow a similar path.

“I just used that as fuel for the fire, to really go out there and prove myself,” said the southpaw of his selection, which came 651 picks after the Nationals took Stephen Strasburg first overall in 2009. “It was a great situation, because there were all new front office people here. They came and talked to us and said ‘We don’t care if you’re a first-round draft pick or a 50^th-round draft pick, everyone is right here,’” he recalled, holding his hand parallel to the ground to show that all players, regardless of their status as an amateur, would be evaluated by the same standards as professionals.

That came as a huge relief to Rosenbaum, who took the message to heart: for better or for worse, nothing you have done to this point matters. Coming off what he considered a disappointing final year at Xavier, it allowed him to have a new approach, one he has carried with him throughout his Minor League career.

“I just try to start each year over from the beginning,” he said. “If I have a good year, great, that’s awesome, but I just try to go back to Spring Training in better shape, with better conditioning, and better stamina than I had the year prior. That’s how I approach every offseason: just work harder than I did before.”

After proving himself over the past few years, Rosenbaum draws rave reviews from anyone and everyone in the Nationals front office. His tough mental approach has led him to become stronger physically as well, something that Harris believes will be the tipping point for his future success.

“He’s a strong-bodied kid,” explained Harris. “His body has continued to evolve. He has a better understanding of what he needs to do, particularly in his core and his lower half to allow him to be as successful as he can possibly be.”

That approach won’t change for Rosenbaum, who has seen his hard work translate not just into numbers, but more importantly, a shot at the ultimate goal of making the Major Leagues.