The Astros (32-50) have scored first against the Pirates (45-36) in all three games of this four-game set, and they've lost all three. The seven-game skid Houston takes into Thursday's 7:05 p.m. ET contest at PNC Park is the Majors' longest current skid.
"Obviously, we didn't get the results we'd like to have gotten," Astros manager Brad Mills said of a trip that started with a three-game sweep by the Cubs.
The Pirates, meanwhile, have shown a strong ability to come from behind, and at nine games above .500 through the halfway point of the season, they're feeling strong.
"It's just good for everybody," Pirates manager Clint Hurdle said of his offense. "You want to look and say: 'Wow, we can do this, or we can do that. OK.' So, we've got more men showing up, offensively. We're competing out of the box. ... You feel confident that everybody out there is going to give you a couple, two to three good at-bats during the course of the game."
An end to the losing ways for Houston could originate in a strong start from Bud Norris, who's up against Pittsburgh's Jeff Karstens in a matchup of right-handers.
Norris is making his second start since returning from the disabled list, where he landed on June 12 with a sprained ankle. He allowed four runs and seven hits in six innings in his last start Friday against the Cubs. All the runs came on home runs.
Of course, that game being a road contest, the Astros fell, 4-0. Norris has losses in four straight outings. That's not the first time he's been streaky this year -- he won four straight in May.
"We've tried to think of possible reasons why [we've played so poorly on the road] and I don't think it's something tangible that we can kind of point toward as a reason," catcher Jason Castro said. "It's frustrating, for sure, and it's something we can hopefully continue to work on."
Karstens is coming off a seven-inning, two-run performance against the Cardinals on Saturday, an impressive game in which he struck out seven. Pittsburgh won 7-3.
Astros: Johnson targeted for Thursday return
• Chris Johnson had two at-bats as a late entry Wednesday into Houston's 6-4 loss to Pittsburgh. He was out of the starting lineup for a fourth consecutive game because of a strained side muscle.
He went 0-for-2, but figures to be able to return to the starting lineup Thursday.
Pirates: Presley slowed by concussion-like symptoms
• Left fielder Alex Presley remained out of the Pirates' lineup Wednesday after leaving Tuesday night early due to concussion-like symptoms. Drew Sutton went 1-for-4 with a strikeout in his place.
Presley made a headlong dive Tuesday in the field and was pulled after four innings. He hasn't been placed on the seven-day disabled list, but that move has not been ruled out.
"It was a whiplash-type scenario. He hit the ground, and his lower torso came up," Hurdle said. "We follow an explicit battery of tests. This is one area in which the player has to interact honestly with the questioning process. It's amazing what kind of a feedback you can get with these tests. They give you a pretty good read on where the player is."
• The Pirates are 5-1 against the Astros entering Thursday, and three series remain between the two teams.