[Updated 5:51 p.m.]
With rookie reliever Abel de los Santos joining the team on Monday, the Nationals made a pair of moves to clear up a roster spot. They transferred Jayson Werth - who is rehabbing a broken left wrist - from the 15-day disabled list to the 60-day DL. They also optioned struggling right-hander Blake Treinen to Triple-A Syracuse.
Werth is playing with the Syracuse Chiefs on Monday night as he continues his road back. He should be able to return soon, possibly within the week, but bringing him to Washington will require a corresponding move on the 40-man roster.
Treinen, 27, leaves the Nationals one day after his worst outing of the 2015 season. He lasted just one-third of an inning and gave up four runs on five hits and a walk to the Dodgers. Treinen left the mound with a 4.39 ERA on the season through 32 appearances.
"For Blake it’s about consistency. We know the kind of talent he’s got. It’s heavy sink coming out of his hand at 97 or 98 mph," Williams said. "The issues that he has had with left-handed hitters this year is something to work on. Yesterday was an example of where he got ahead but he just couldn’t finish."
Treinen entered the season with expectations to take on a significant role in the Nationals' bullpen after an impressive showing in 2014 as a rookie. He held a 2.49 ERA in 15 outings including seven starts. Treinen strung together six scoreless appearances heading into the All-Star break before his unfortunate showing in Sunday's 5-0 loss.
"We’ll give him an opportunity to get down there and 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. He’ll just work on some things and be back here quickly," Williams said.
De Los Santos joins the Nats after posting a 2.65 ERA in 26 games with the Double-A Harrisburg Senators. The right-hander was acquired over the offseason in a three-player trade with the Texas Rangers in December.
"We didn’t get a chance to see him in spring training. But we certainly have reports from everybody that has seen him within the system," Williams said. "He’s been closing some games for them pitching high leverage situations and back of the bullpen situations for them. Everybody loves his stuff. He’s got good stuff, throws strikes. Got a breaking ball to go a long with it that he can spot when he needs to do so he’s been doing well."