Who is Washington Nationals rookie Abel De Los Santos?

The Washington Nationals will reportedly promote right-handed pitching prospect Abel De Los Santos to the major league roster today. De Los Santos is not exactly a household name, but he is actually a fairly interesting relief prospect who could be valuable. Let's take a look.

De Los Santos was signed by the Texas Rangers in 2009 from the Dominican Republic. His track record in the lower minors was erratic; he pitched well in the Dominican Summer League in 2010 and the Arizona Rookie League in 2011, but was lit up as a starter in the Northwest League in 2012. He converted to full-time relief work in 2013 and was more successful. His 2014 season was quite good (1.92 ERA, 65/18 K/BB in 56 innings between Low-A and High-A.

This caught the eye of the Nationals and he was included in the December 2014 Ross Detwiler trade. His performance in 2015 has been very sharp: 2.65 ERA, 35/7 K/BB in 37 innings for Double-A Harrisburg, just 26 hits allowed, collecting six saves.

This video from Nate Stoltz is a year old but gives the general idea of how ABDL looks on the mound.

De Los Santos is a 6-2, 195 pound right-hander, age 22. When used as a starter in the lower minors his fastball was in the 89-93 range, but with physical maturity and the switch to the bullpen he can hit the mid-90s now. He's made strides with his slider and his control has improved significantly over the last two seasons. His command within the strike zone isn't perfect but the complete package is very tough on right-handed hitters: they're hitting just .164 against him this season.

Right now this is a classic middle relief profile, but continued progress with his command could get him a larger role at some point down the line.