Billy Traber, LHP (3-3, 7.36)
..... Claudio Vargas, RHP (11-9, 4.90)
Traber, who has mild left shoulder soreness, is expected to pitch against the Diamondbacks on Monday. In his last start, Traber lasted four-plus innings while giving up four runs on 10 hits. All four runs could have been avoided if Traber had received better defensive support.
Vargas enjoyed one of his strongest outings of the season and the third win in his past four decisions in his last start against the Marlins. Though he got into trouble in the sixth, allowing two runners on with one out, Vargas enjoyed an otherwise relatively drama-less outing. The right-hander tied a season-high by throwing seven shutout innings on four hits with six strikeouts. Vargas, a former National, has never faced Washington before.