The Nationals optioned struggling reliever Aaron Barrett to Triple-A Syracuse and called up right-hander Blake Treinen to take his place on Thursday, fresh off Barrett taking the loss against the Arizona Diamondbacks the previous night.
Barrett gave up three runs in Wednesday’s defeat including two on a throwing error to first base on a bunt by Nick Ahmed. He has a 4.60 ERA through 40 appearances this season.
Treinen, 27, rejoins the Nationals after getting sent to Syracuse in July. He made five appearances with the Chiefs and did not allow a run in 12 total innings of work.