Date/Location of Birth: September 29, 1987 in Richmond, Virginia
Height/Weight: 6'1", 190 lbs.
Position: Starting Pitcher
Throws: Right
Stoneburner (which, coincidentally, means "Steinbrenner" in German) fell to the 14th-round of the 2009 draft because of "signability" and a significant injury history. He missed his whole senior season of high school due to a fractured vertebra. Baseball America rated him the 71st best prospect heading into the 2006 draft but he ended up not being picked by any team. He then tore his ACL in his freshman year at Clemson University, causing him to miss another season. In two college seasons following that, he had an up and down time of it, mixing starts with relief appearances. BA still ranked him the 180th best prospect entering the '09 draft.
The 23-year-old has exceeded expectations in his brief pro career. After being selected 435th overall by the Yankees two years ago, he signed late and well above slot ($675K) and only threw one inning that year. He made his full-season debut last year and had one of the best seasons in the whole system: 142 ip, 2.41 ERA, .993 WHIP, 8.7 K/9 and 2.2 BB/9 between Low and High-A.
Stoneburner is still rockin' a great ERA in the early going at Trenton (1.69), but it belies his decreased K-rate and higher WHIP. If he was 2-3 years younger, he'd be a top five Yankee prospect and a top 100 MLB prospect.
Unfortunately, he's been on the DL since April 22 with a "stiff neck" and is rehabbing in Tampa. It shouldn't be long, though, before he returns to the Thunder rotation.
His arsenal features a low to mid-90s sinking fastball - he's managed a groundball rate better than 50% in 150+ pro innings so far. His secondary pitches include a changeup and an improving slider. His best asset (aside, obviously, from a 95-MPH sinker) is his control (2.2 BB/9 career) and mechanics, which apparently are very smooth and should ensure a healthy future. (The "good" news about his prior injuries is that they had nothing to do with his arm.)
ETA: I expect he'll be in Trenton most, if not all, of 2011. Come 2012, he'll be considered around mid-season if the Yankees need a starter, but 2013 will most likely be his ETA, at least for anything more than some spot-starts.
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