SAN DIEGO -- The turning point in a rare home win for the San Diego Padres came when manager Bud Black was ejected by plate umpire Greg Gibson in the top of the fourth inning.

"We turned around and scored some runs. It fired everybody up," winning pitcher Dustin Moseley said after the 3-1 victory against the Houston Astros. Chris Denorfia homered and the Padres won for just the 10th time in 31 home games.

The crowd certainly got fired up. Black was ejected while in the dugout, then came out to argue with Gibson.

"It got everybody rocking and rolling," Moseley said. "It was good. It definitely helps when you've got your fans behind you and you have some energy flowing. Guys can feed off that."

Black was ejected for saying something to Gibson during an at-bat by Astros starter J.A. Happ, who struck out to end the inning.

"I thought that was a quick toss for Buddy for what he said," Moseley said. "I don't think he said anything real rude."

It was a matchup of the two worst teams in the NL. The Astros had their season-long four-game winning streak snapped.

Moseley (2-6) earned his first win at Petco Park by holding Houston to one run and six hits in seven innings, with five strikeouts and one walk. Heath Bell pitched the ninth for his 15th save in 16 chances.

Denorfia hit a 2-1 pitch from Happ to center field with two outs in the fifth, his fourth, to give the Padres a 3-1 lead.

"That was a bullet -- from TV," said Black, who watched from his office. "It would have been more of a bullet from the dugout. TV doesn't give that one justice, I don't think. I wish I would have saw that from the dugout."

The Padres had gone up 2-1 in the fourth on four hits, which for them is sometimes a game's worth at Petco Park. Jason Bartlett had a leadoff infield single and Chase Headley singled up the middle to extend his hitting streak to 13 games. Ryan Ludwick singled up the middle to bring in Bartlett while Headley was thrown out trying to take third. With one out, Aaron Cunningham doubled into the left-field corner to bring in Ludwick, who has 26 RBIs in his last 31 games.

Houston got its run in the fourth when Chris Johnson hit his second straight triple and scored on J.R. Towles' suicide squeeze.

The Astros had runners on third in each of the first three innings before stranding them. They were 0 for 7 with runners in scoring position.

"We didn't have too many chances tonight," Johnson said. "But we're not going to dwell on it. We'll forget about it and start a new streak tomorrow."

Happ (3-7) tied Pittsburgh's Paul Maholm for the most losses in the NL. He went six innings, allowing three runs and six hits, with two strikeouts and two walks.

Game notes
Padres C Nick Hundley, on the disabled list since May 5 with a strained muscle in his right side, will begin a rehab assignment at Triple-A Tucson on Saturday. ... Johnson was the first Astros player with two triples in one game since Billy Hatcher had two on June 1, 1989, against Los Angeles.