Strasburg's 44th pitch of the afternoon set down Astros shortstop Marwin Gonzalez swinging, and that marked the end of his day.
The right-hander finishes having thrown 2 2/3 innings, allowing two runs on three hits and a wild pitch. Strasburg had three strikeouts, two of which were swinging.
He allowed a solo home run to catcher Chris Snyder with one out in the second, and was on the hook for another run when Tom Gorzelanny gave up a three-run shot to J.D. Martinez.
Of Strasburg's 44 pitches, 26 were strikes.
Other than the Snyder home run, Strasburg allowed two doubles - one by Fernando Martinez on a sharp line drive to left-center, and the other on a bouncing ball down the first-base line by Jordan Schafer.
Strasburg bucked the knees of first baseman Chris Johnson with a nasty curve in the third inning and earned a called third strike.
The Nats trail 4-1 after three innings. Jason Michaels delivered the lone Washington RBI.
Dan Kolko was named MASNsports.com's Nationals beat writer after spending the last four years covering the Baltimore Ravens for MASN and also serving as the Web site's deputy managing editor. A University of Delaware graduate originally from Silver Spring, Md., Dan grew up a die-hard baseball fan and is thrilled for the opportunity to cover the Nationals. Before joining MASN, Dan worked in production at Comcast SportsNet in Bethesda, Md., and also interned at the "George Michael Sports Machine" in Washington, D.C.