[Updated 7:06 p.m.]
Aaron Barrett is back on the 15-day disabled list with a right elbow strain, just three days after he was sent to Triple-A Syracuse.
The Nationals voided his option to make the move with Barrett needing a DL stint for the second time this season. Barrett also spent time on the shelf in June with a right bicep strain. The right-hander has a 4.60 ERA in 40 appearances.
"He'll get some tests," Matt Williams said. "We decided to option him and then he let us know his elbow was bothering him. He didn't let us know anything until then. Since then we've scheduled some tests, put him on the DL to make sure we get a look at it.
Barrett was sent to Triple-A after giving up three runs in just 1/3 of an inning against the Arizona Diamondbacks on Aug. 5. Prior to that he had pitched nine consecutive scoreless appearances. The Nationals called up right-hander Blake Treinen to take Barrett's place on Aug. 8.
This season has been a trying year for Barrett, who was surprise contributor in 2014 as a rookie. Last year he held a 2.66 ERA in 50 games and earned a spot on the Nationals' playoff roster. He entered this season with hopes of taking another step, but so far that hasn't happened.