PHOENIX -- Morgan Ensberg is putting up some impressive numbers. Still, the only ones he cares about are in the standings.
"Individual accolades are something that when your career is over you can look back on," said Ensberg, who finished 3-for-4 with two runs. "What I'm excited about is how the team's playing as a team. We're a team of nobodies and we're playing solid baseball."
Ezequiel Astacio (2-4) won his second straight decision for the Astros, who won for the 15th time in 17 tries to maintain a two-game lead over Washington in the NL wild-card race.
Astacio scattered four hits, three of which never left the infield, and allowed only one runner to reach third base. He walked three and struck out one in five innings.
"He did a good job of making pitches when he needed to," Astros manager Phil Garner said. "We'd like to see him pitch ahead a bit more. He got behind a lot of hitters. But he did a pretty good job of making the pitches when he had to."
Astacio, who has allowed three runs or fewer in all four starts since being recalled from Triple-A Round Rock, credited catcher Brad Ausmus with his turnaround.
"(Garner) told me he's been in the big leagues a long time and to listen to him," Astacio said. "He's taught me a lot."
Arizona lost for the fifth time in seven home games and squandered a chance to move into a first-place tie with San Diego in the NL West. The Padres lost 9-8 to Pittsburgh before the Diamondbacks took the field.
Astacio was in trouble only once, when consecutive infield hits with one out and a line-drive single loaded the bases in the fourth. But he struck out Chris Snyder and retired pitcher Javier Vazquez on a fly to center.
Houston took a 1-0 lead in the second on Chris Burke's sacrifice fly, then broke the game open with a four-run sixth against Vazquez (9-10).
Ensberg led off with a 450-foot shot off the batter's eye in center, and a bloop RBI double by pinch-hitter Orlando Palmeiro with two outs made it 3-0.
Vazquez allowed five runs -- two earned -- and nine hits with five strikeouts in 5 2-3 innings.
"We all didn't play well today," Arizona's Luis Gonzalez said. "We didn't make plays behind him when we had to and we didn't get hits. We didn't score runs. You can't win with zero runs."
- The Astros have seven pinch-hit doubles, a franchise record.
- Gonzalez ran full speed into the left-field fence to catch Jason Lane's drive in the fourth. Gonzalez appeared shaken but remained in the game. "I thought that was really going to be an emotional play in the game for us," manager Bob Melvin said.
- Astros 1B Lance Berkman was scratched from the lineup shortly before the first pitch with an undisclosed illness and replaced by Mike Lamb.
- Arizona RHP Russ Ortiz, making a rehab start at Class-A Lancaster, allowed 10 runs and 12 hits in 2 1/3 innings. Ortiz has been on the disabled list since June 16 with a stress fracture of his right rib cage.