ATLANTA -- The Atlanta Braves made a flurry of trades on Tuesday, but a bolstered roster can't be blamed for the Astros loss.

Two of Atlanta's three new additions were not at this game, and for the first 90 minutes of the opener with the Astros, they were short one player, because newly acquired first baseman Mark Teixeira wasn't due to arrive to Turner Field until 9 p.m. ET.

Still, the 24 Braves on the roster were able to top the Astros, 12-4, thanks to some well-timed home runs that negated a so-so performance from their starting pitcher.

"We stunk, they won, and that's it," manager Phil Garner offered.

The Astros tagged Chuck James, who was relatively untouchable for his previous five outings, for four runs over five frames. But the Braves were more productive against Houston starter Chris Sampson, who allowed two home runs and gave up five through four innings of work.

Sampson wasn't the only one to blame. The bullpen wasn't much better, and the defense seemed to have taken the night off as well.

"For some reason, nobody could throw a good breaking ball," Garner said. "We kept missing with our breaking balls, we didn't have good ones, and they didn't miss them. When we made mistakes, they hit them. And when we had the ball over the plate, they hit it. We did a lot of that."

The Astros scored a run in the first, behind Lance Berkman's 17th homer of the year. But the Braves answered with two in the second, thanks to a Brian McCann solo homer and a sacrifice fly from Julio Franco.

The Braves never relinquished the lead. They scored one in the third on Andruw Jones' sac fly, and they increased their lead to four runs on Kelly Johnson's two-run homer off Sampson in the fourth.

Sampson has a 1-3 record and a 6.14 ERA over four starts in July. He's allowed at least four runs in three of those four outings, and he hasn't pitched past the fifth inning in his last two.

Garner acknowledged that he's concerned that Sampson, who has thrown 117 1/3 innings, may be fatigued. Garner does not feel the rookie is injured.

"I don't know that it is [an injury]," Garner said. "He's had aches and pains. Right now he's not telling us he's injured but he has aches and pains. Tonight, he had trouble with his breaking ball. He never did find a good slider, good curveball."

Sampson echoed the skipper's comments, first about the quality of his pitches and then about his health status.

"The sinker wasn't sinking, the slider wasn't really sliding, the curveball was off and on," Sampson said. "I threw a lot of good ones and a lot of bad ones. To make up for the sinker not sinking, I tried to make sure it was down in the zone. It was a little too down and the result was falling behind in the count a little bit. It's tough to pitch when you're always behind."

On the question of fatigue, Sampson responded: "Every pitcher's arm is going to be not 100 percent. They don't call them dog days of summer for nothing. Hopefully we just push through, catch a second wind and get back on track. That's all we need to do.

"If I was hurting, I'd tell you."

The Astros came back with three in the fifth, behind a pinch-hit RBI single from Chris Burke and a two-run double by Craig Biggio, his 662nd career two-bagger.

But Johnson's three-run shot off Matt Albers in the seventh put the game out of reach. Prior to this outing, Albers had held opponents to one run over five relief appearances.

"Same thing with him -- he couldn't get his breaking ball over, so he's left with his fastball, and everybody in this league hits fastballs if you have nothing to get them off of it," Garner said. "This whole league's hitting fastballs well right now. They're jumping all over it."

Said Albers: "I was missing with my fastball, just low a bit. Coming off the ball, I was overthrowing a tad. I missed down a little bit. I got behind a couple good hitters."

The Braves piled on two more runs -- both unearned -- in the eighth off Brian Moehler. Eric Bruntlett made two errors in that inning to cap a three-error night.

"I was horrible," Bruntlett said. "I couldn't do anything well tonight. That's one of those times where you want to find a hole and hide yourself in it. Unfortunately, there are none out there, so you have to bear it and hope the pitcher gets out of it. It seems like it never works out that way. It was not a fun night for the team, and especially for me tonight."