With the win, Houston moved to within four games of the first-place Cardinals in the National League Central, and matched its longest winning streak since August 2011.
Astros manager Brad Mills doesn't believe it's too early to look at this series as a measuring stick for his club.
"I don't think it's too early at all," Mills said. "I want our guys to come out and play good solid baseball. They have lately, but there's always things we can tweak and try to get better. That's what we want to do."
The Cardinals, losers of two straight, have played 25 consecutive games against division opponents, going 15-10 against NL Central rivals on the year.
Jaime Garcia, who is 2-1 with a 2.78 ERA this season, gets the ball for the Cardinals on Saturday having pitched at least seven innings in each of his last three outings. He has not allowed more than three runs in any of his five starts.
The left-hander has had difficulty with the Astros throughout his career, however, as he's 0-3 with a 6.39 ERA over five starts against them, but he has an offense that has scored the most runs in the league to help him out.
"When everybody in our lineup is going good, we're as good as anybody in baseball," Matt Carpenter said Wednesday night. "There's not an easy out in that lineup."
Houston's Bud Norris will counter the southpaw, and he's 1-1 with a 5.46 ERA in five starts this season. The 27-year-old is 6-2 with a 2.37 ERA in 10 career starts against the Cardinals.
Cardinals: Craig making impact
Allen Craig, who missed all of April recovering from offseason knee surgery, has produced immediately after seven rehab games in the Minor Leagues.
Craig was held hitless on Friday after collecting multiple hits in his first two games of the year, but he drove in a run for the third consecutive game in his first start batting cleanup.
Carlos Beltran wasn't in the starting lineup for the second consecutive game on Friday after feeling tightness near his hamstring during workouts Thursday, but pinch-hit in the eighth inning.
"He said it wasn't that big of a deal and could go," Cardinals manager Mike Matheny said. "But we're going to have to be careful this month. We've got one off-day, so we're really going to have to be searching and listening to when these guys need a day [off]. I think we all know that keeping them healthy is the key."
Astors: Houston's offense a pleasant surprise
The Astros have been among the the top offensive teams in the NL, as they've scored the fourth-most runs in the league and have the second-highest on-base percentage.
Houston, which won just 56 games last season, trails St. Louis in both categories and in the standings, but Astros outfielder Jordan Schafer believes his team can compete.
"We have a lot of young guys showing they belong in the big leagues," Schafer said. "It's nice to see we're getting some results."
Schafer reached base for the 25th consecutive game to open the season on Friday, tying the club record set in 1969 by Denis Menke.