The past was prologue tonight as the Giants in the middle innings struggled to get out from under the disaster that was the first inning. Later in the season, if the past is prologue, the Giants will be in trouble should they face the Nationals in October baseball.

Matt Cain toed the hill for the Giants, and promptly he walked the bases loaded to start the game. All three runners scored, and the Giants played catch-up all night though they never equaled those three runs. The final was 6-2, and the Nats took the series by winning its first three games. Tanner Roark has pitched outstanding baseball, so, with him on the hill, overcoming a 3-0 deficit became a tall order, too tall for the Giants.

The Nats showed glove in their victory. Danny Espinosa, the second sacker, robbed Gregor Blanco of a single in the fourth that would have changed the score, and Ryan Zimmerman lunged to catch Brandon Crawford’s shallow flyball in the sixth. Zimmerman has converted to center field from third base, and that conversion has been so complete that the return of Bryce Harper and his remarks about returning to center field have become problematic.

Perhaps baseball is a game of streaks or momentum. If that is so, the Nationals seem to be surfing atop them.