John Beck, was 4 of 6 for 46 yards and led one touchdown drive.
Undrafted rookie Case Keenum, the NCAA's career leader in yards passing, touchdowns, and completions at the University of Houston, completed 2 of 3 passes for 33 yards for the Texans.
Houston's defense, which finished second in the league last year, registered eight sacks — five of those on Jimmy Clausen.
"The first unit played only 12 or 15 plays, but we played well as a group," said Texans linebacker Connor Barwin. "Obviously, there were some mistakes — not a lot. It was really encouraging to see some of the young guys step up when they have their chance. We had eight sacks, which was really impressive."
Houston's only offensive touchdown came on rookie Jonathan Grimes's 3-yard run.
For the most part, Carolina fans didn't have much to cheer about.
But rookie Joe Adams, the team's fourth-round draft pick, gave the crowd a thrill when he changed field, avoided several tacklers and returned a punt 39 yards in the fourth quarter. The Panthers have ranked near the bottom of the league in punt return average the last several years and hope Adams can give them a spark in the return game.
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