Saccomanno hit a solo shot in the fifth inning, becoming the fourth Houston player to homer in his first big league plate appearance. The Astros have won three straight and 11 of 12 to move 10 games over .500 for the first time this season.
Called up from the minors earlier in the day to help fill in for injured third baseman Ty Wigginton, Saccomanno batted for pitcher Alberto Arias in a scoreless game and drove Ian Snell’s pitch into the right-field bullpen.
The homer triggered a three-run inning for the Astros. The next four batters got hits, including RBI singles by Miguel Tejada and Lance Berkman.
The last Houston player to homer in his first career plate appearance was Charlton Jimerson on Sept. 4, 2006, at Philadelphia.
Arias (1-0) gave up two hits in five impressive innings. It was his first major league start after 18 relief appearances with Colorado.
Arias started strong, striking out five of his first six batters. He didn’t allow a hit until Nyjer Morgan led off the fourth with a single to right.
Moments later, Arias threw wildly past Berkman trying to pick off Morgan at first. Morgan nearly circled the bases, but Berkman threw him out at the plate.
Arias walked three and struck out six. He started in place of Brandon Backe, who was scratched because of soreness in his arm during a bullpen session Saturday.
LaTroy Hawkins pitched a scoreless eighth. He has not allowed a run in 16 games since coming to the team in a trade with the New York Yankees on July 30.
Jose Valverde pitched the ninth for his National League-leading 41st save in 47 attempts. He has recorded saves in a club-record 14 straight appearances.
Snell (6-11) went six innings, allowing three runs and six hits. He walked three and struck out nine.
Ryan Doumit and Adam LaRoche hit consecutive RBI singles for the Pirates in the sixth.
