In the bottom of the third inning, the Nationals had Wil Nieves on third with one out. He didn't score.
They got Ian Desmond there with one out in the fifth - after a double that could've been a game-tying homer had it gone a foot in any other direction. He didn't score, either.
They had runners on first and second with one out in the sixth. Nothing there, either.
So the Nationals trail 1-0 in the top of the seventh, despite Livan Hernandez settling into a nice groove and Johan Santana offering up his fair share of appetizing fastballs. It's why they spend so many nights being confounded about losing games in spite of all the hard-hit balls they put into play - because eventually, somebody has to drive in runs.
Right now, this team can't do it, and they're running out of time to avoid their seventh loss in eight games.