SAN DIEGO (AP) -- The Houston Astros suddenly seem to be a different team.
Chris Johnson homered and the Astros used a five-run third inning to beat the sloppy San Diego Padres 7-4 on Thursday night in a matchup of the NL's two worst teams.
The Astros (23-34), last in the NL Central, have won the first four games of a seven-game trip, their longest winning streak of the season. The Padres (24-33), last in the NL West, dropped to 9-21 at home, worst in the NL. They came in hitting a major league-worst .199 at home.
"It's good to get some stuff going," Johnson said. "It's kind of one those things that we know we're capable of doing this. It's almost an about-time feeling that we're doing this."
The Astros didn't have any trouble with spacious Petco Park. Johnson homered to left on a 1-0 pitch from Tim Stauffer (1-4) with one out in the fifth for a 7-2 lead. It was Johnson's sixth. That helped make a winner of Bud Norris (3-4).
"It's one of those parks where you try not to think about hitting the ball out of the ballpark here just because it's a big yard, but he left a changeup out over the plate and I got some backspin on it and got it out," Johnson said.
Norris went six-plus innings, allowing four runs and six hits while striking out six and walking two. Mark Melancon pitched the ninth for his fifth save in seven chances.
The Astros had 11 hits. Hunter Pence extended his hitting streak to 14 games with a third-inning single.
"We're doing a lot of the little things right," Johnson said. "We're coming up with some timely hitting and getting good pitching. When you do those things, it's easy to win games."
Houston jumped on San Diego for five runs on just three hits in the third, when the Padres committed three errors, including a catcher's interference. The first four Astros reached and scored, and Houston sent 10 men to the plate.
Carlos Lee had an RBI double and Brett Wallace an RBI groundout. J.R. Towles was credited with an RBI when shortstop Jason Bartlett bobbled his slow grounder, allowing Towles to reach and Lee to score. Norris drove in a run with a fielder's choice and another run scored on the play on second baseman Logan Forsythe .
"Bad inning," Padres manager Bud Black said. "Any team that commits three errors in an inning and gives up three hits, there are going to be a number of runs scored. That got us behind the eight-ball and we couldn't quite recover. That inning did us in."
Johnson also had an RBI single in the second.
Stauffer allowed seven runs, five earned, on eight hits in five innings, struck out four and walked two.
The Padres got consecutive RBI singles by Chase Headley , who extended his hitting streak to 12 games, and Ryan Ludwick in the third, and consecutive sacrifice flies by pinch-hitter Chris Denorfia and Eric Patterson in the seventh.
NOTES: The Padres said nearly 1,000 season-ticket holders donated their tickets to military members and their families. Of those, 32 were in the Sony Home Plate Club, which at $325 are the most expensive seats at Petco Park. ... Padres manager Bud Black said C Nick Hundley , on the disabled list because of a strained muscle in his right side, will do drills on Friday and if everything goes well, will begin a rehab assignment at Triple-A Tucson. ... It was the seventh straight road game in which the Astros have 10 or more hits