Mark Loretta walked and was hit by a pitch during a wild sixth inning, and the Houston Astros beat the San Francisco Giants 6-2 Wednesday night for their season-high seventh straight victory.

The Astros scored six times in the bizarre sixth. San Francisco tied a major league record by hitting three batters in the inning, and also issued four walks.

Houston's winning streak is its longest since a nine-game string in September 2006. The Astros have won 15 of 19 overall.

Randy Wolf (8-10) didn't allow a hit until Fred Lewis' leadoff single in the fourth. He improved to 2-0 in four starts since the Astros acquired him from San Diego on July 22.

Barry Zito (6-15) shut out the Astros on two hits through five innings. But the Giants' 1-0 lead quickly disappeared when Zito and reliever Billy Sadler lost their control.

In all, the Astros' six runs were driven in by two hit batters, two walks and two sacrifice flies.

Ty Wigginton hit a leadoff single, Mark Loretta walked and Miguel Tejada blooped a single to center that loaded the bases. Lance Berkman drew a walk that tied the score and sacrifice flies by Geoff Blum and Reggie Abercrombie made it 3-1.

After Zito hit Humberto Quintero with a pitch to reload the bases, he walked Wolf to force home another run. Sadler took over and hit the first two batters he faced, Wigginton and Loretta, to make it 6-1.

It was the 35th time in major league history a team has hit three batters in one inning, and the first since San Diego was plunked three times by the New York Mets on June 7.

Randy Winn and Bengie Molina doubled in the sixth for the Giants' first run. Winn and Ryan Rohlinger each doubled in the seventh. It was Rohlinger's first major league hit.