With Tuesday's opener against the Dodgers postponed until Wednesday, manager Davey Johnson will have to make an adjustment in his starting rotation later on in the week.
According to Johnson, Wednesday's starters will be Jordan Zimmermann for the 4:05 p.m. start and John Lannan for the second game.
With no days off the rest of the regular season, that leaves an opening down the line for Sunday's game against the Milwaukee Brewers. Zach Duke, Craig Stammen, Tom Gorzelanny and Chien-Ming Wang are a few of the options available to Johnson.
"With the doubleheader, I probably need to plug somebody in," Johnson said. "(Zach Duke) is a candidate. I will need one Sunday, if we play two tomorrow. Also, I haven't done my research on those matchups, but knowing what I know about Milwaukee, it could be (that) I start somebody out of my pen. I have a right-hander in Craig Stammen, he could be a candidate, or Chien-Ming Wang."
Johnson confirmed he would not call anyone else up from Triple-A Syracuse to make a spot start because of the rain out.
But Stammen or even Gorzelanny may seem more likely because Johnson doesn't want to tax his four starters.
"I won't start anyone on three days rest, so I will definitely go to the pen," Johnson said.
"I just don't want any of my good young pitchers to be brought back on short notice. I don't think Zimmermann has done it, and he has had a little bit of that inflammation. I think he could do it and have no problem, but it's not something I would like to any of those (pitchers) in the rotation at this point (to have to do)."
Left-hander Duke went 15-5 in 26 starts for Triple-A Syracuse, with 3.51 ERA and 91 strikeouts. Duke is 0-0 in two games with the Nationals in relief appearances, allowing one run on three hits in 4 2/3 innings, for a 1.93 ERA.
Stammen has been exclusively out of the bullpen this season, but came into the majors as a starter, with 38 starts, including 19 starts in 2010. He made 24 starts for Triple-A Syracuse in 2011. Stammen is having a career year with six wins and a 2.39 ERA in 53 games.
Wang is 2-3 with a 7.61 ERA in seven games this season, four of those starts. He made 15 starts this summer in minor league rehabs, going 4-6 with a 5.51 ERA. Wang allowed six runs in each of his last two starts for Double-A Harrisburg.
Keeping the mood light, Johnson said he did have one other option he was considering for a spot start, an up-and-coming talent named Stephen Strasburg.
"I am sure Stras would volunteer, he is right-handed, he has been chomping," Johnson joked.