Houston right-hander Livan Hernandez was on the mound when Washington scored in the first inning. With two outs, Zimmerman swung at a pitch and hit a solo home run over the right-field wall against his former teammate.
In the next inning, Eury Perez made it a 2-0 game when he singled to center, scoring Brett Carroll. Hernandez would leave the game in the next inning when he was hit on the right leg by a line drive off the bat of Zimmerman. Hernandez was able to walk off the field under his own power. The injury is not considered serious.
The Nationals scored their final six runs in the fifth, sixth and seventh innings. With Henry Sosa on the mound in the fifth, Zimmerman had an RBI single, while Mark Teahen scored on a single by Jason Michaels.
The Nationals added three more runs in the next inning. Anthony Rendon highlighted the scoring with an RBI double. Washington scored its final run in the seventh inning when Carlos Rivero scored on a groundout by Carroll.
Nats starter Edwin Jackson scattered just two hits over four scoreless innings, and the Astros amassed a total of three hits in the game.
Up next: Stephen Strasburg is expected to make his second start of the spring Friday night against the Marlins at 7:05 p.m. ET. Strasburg is expected to throw 60 pitches. Shortstop Ian Desmond will be the only regular position player who will start the game in Jupiter, Fla.
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the time. He also could be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.