"[Abel] de Los Santos is a starter-made-reliever and since he's gone to the bullpen his velocity and stuff has spiked," Washington Nationals' GM Mike Rizzo told reporters this winter after he acquired de Los Santos and minor league infielder Chris Bostick from the Texas Rangers in return for left-hander Ross Detwiler
"[de Los Santos] had a terrific year last year and we think that he'll come really quickly," Rizzo said.
In 26 games with the Double-A Harrisburg Senators in his first season with the Nationals, de Los Santos, (who was (5-2) with eight saves in 33 appearances for High-A Myrtle Beach last season in the Rangers' system, with a 1.97 ERA, a 2.93 FIP, 17 walks (3.35 BB/9) and 53 Ks (10.45 K/9) in 45 ⅔ innings pitched), was (4-4) with a 2.65 ERA, 2.68 FIP, seven walks (1.69 BB/9) and 35 Ks (8.44 K/9) in 26 games and 37 ⅓ innings pitched before he was called up to the majors on Monday, with Blake Treinen optioned to Triple-A.
Treinen, 27, struggled with his command, walking 4+ batters per nine innings and had trouble against left-handed hitters this season, who put up a .346/.427/.513 line against the right-hander in 89 plate appearances.
Overall, the sinker-balling reliever went down to Triple-A with a 4.39 ERA, a 3.16 FIP, 44 Ks (9.66 K/9), 21 walks (4.61 BB/9) and a .272/.363/.378 line against in 41 innings pitched.
"For Blake it's about consistency," second-year skipper Matt Williams said after the move was announced.
"We know the kind of talent that he's got. It's heavy sink coming out of his hand, and at 97 or 98 mph. The issues that he's had with some left-handed hitters this year is something to work on.
"[Sunday] was an example of where he got ahead, but he just couldn't finish. So we'll give him an opportunity to get down there, get that consistent work and get him stretched out if we can.
"He'll be able to go down and throw three innings if we needed him to do that, he's perfectly fine to do that, but he'll just work on some things and be back here quickly."
As for de Los Santos, Williams said he hasn't seen much of the right-hander, but the reports have all been good.
"We don't know a lot because he's new to the organization this year," Williams explained.
"We didn't get a chance to see him in Spring Training, but we certainly have reports from everybody that's seen him within the system.
"He's been closing some games for [Harrisburg], pitching high-leverage situations and back-of-the-bullpen situations for them. Everybody loves his stuff. He's got good stuff, throws strikes and has got a breaking ball to go along with it that he can spot when he needs to, so he's been doing well."
The 22-year-old right-hander will get a chance to show what he can do at some point in the near-future. He spoke to reporters before Monday night's game about what has been working for him this season.
"When I was in Double-A, my fastball was good," de Los Santos said. "Good command on both sides of the plate."
• Minor League Ball's John Sickels took at look de Los Santos today too. Check out his scouting report on the right-hander through the link below: