Houston, TX (Sports Network) - Darnell McDonald's three-run homer came during a four-run eighth inning as Boston toppled Houston, 10-4, in the second edition of a three-game interleague series.
Adrian Gonzalez, Kevin Youkilis and Dustin Pedroia all collected three hits and drove in a run apiece for the Red Sox, winners of three straight games.
Yamaico Navarro's first hit of the season was his first career home run, while David Ortiz and Jarrod Saltalamacchia also knocked in runs for Boston.
Andrew Miller (2-0) worked six innings for the win, giving up seven hits, two runs and two walks with three strikeouts.
Hunter Pence finished 3-for-4 with a home run and two RBI for the Astros, who have dropped 10 of their last 12. Michael Bourn tied a career high with four hits and scored pair of runs in the loss.
J.A. Happ (3-10) lasted 6 2/3 frames in defeat and was touched for seven hits and five runs while walking three and fanning as many batters.
A four-run eighth inning provided key separation for the visitors against Fernando Abad.
Three straight singles -- from Gonzalez, Youkilis and Josh Reddick -- loaded the bases before Saltalamacchia's sac fly to left plated a run and McDonald followed with a three-run blast inside the left-field pole to make it 9-3.
Youkilis put the BoSox in double digits with a ninth-inning single to bring in Gonzalez, who doubled in the previous at-bat. Matt Downs singled in Bourn during the Houston ninth but it wasn't nearly enough.
The Sox dented Happ for three runs in the first, on a Gonzalez RBI single, an Ortiz walk with the bases loaded and a double-play grounder from Saltalamacchia. The Astros countered in the home portion when Bourn led off with a triple and scored on an Angel Sanchez base hit.
In the fifth, Jacoby Ellsbury doubled inside the first-base bag and scored when Pedroia followed with a double for a 4-1 Sox edge, but Pence hit a solo shot to left to start the sixth.
Navarro followed with a pinch-hit solo homer to left-center for a 5-2 Boston lead in the seventh, and the visitors dodged a bullet in the bottom half as Pence's bases-loaded, two-out walk was the lone damage against a shaky Alfredo Aceves and a steadier Daniel Bard.
Boston has beaten Houston in six of the last eight matchups since June, 2003...The last Red Sox player to hit his first career homer in a pinch-hit situation was Juan Diaz on June 23, 2002...Bourn extended his hit streak to 11 games...After managing only 15 runs in seven games from June 21-29, the Red Sox have exploded for 22 runs during their current win streak.