Houston's offense struggled for the better part of three quarters, but the defense did what it has done so far this season - create turnovers.
John O'Korn threw for 198 yards and a touchdown and Kenneth Farrow ran for two second-half touchdowns as Houston overcame a slow start to defeat Memphis 25-15 and remain undefeated.
O'Korn finished 13 of 30 and Deontay Greenberry caught four passes for 76 yards for the Cougars (5-0, 2-0 American), who were out-gained 349 yards to 247.
Houston, which is 5-0 for the fourth time in school history and the second time in three years, has already tied its win total from last year when it finished 5-7.
"It wasn't pretty," Houston head coach Tony Levine said. "It wasn't perfect. It may never be perfect. I am really proud of our defense creating those four turnovers. Offensively, we have to turn those turnovers into points, and we weren't able to do that consistently."
Paxton Lynch was 21 of 41 for 222 yards passing, and Brandon Hayes rushed 12 times for 72 yards to lead the Tigers (1-4, 0-2), who committed four turnovers - all fumbles. Mose Frazier caught five passes for 81 yards.
Jake Elliot tied a school record set by Ryan White in 1999 with five field goals for Memphis.
"I felt comfortable," Elliot said. "The grass was an adjustment, playing on turf all the time. But we have very similar grass on our practice field, so that was helpful. The field was getting torn up a bit, so I had to make adjustments there."
Houston has forced 18 turnovers this season.
"It's a different look," Houston linebacker Efrem Oliphant said of the Cougars defense. "Everybody expected them to score I'm sure. They haven't focused on Houston being a defensive team, so that should open eyes that we are playing defense."
Trailing 15-10 midway through the third, Farrow put the Cougars ahead with a 1-yard run and followed that by taking O'Korn's shovel pass in for a two-point conversion, capping a 7-play, 75-yard drive.
O'Korn found Greenberry for 30 yards to begin the drive, and the Cougars were able to keep it going with a penalty by Memphis on a fourth and 4. O'Korn found Xavier Maxwell for a diving catch good for 33 yards to the 1-yard line and Farrow ran it in on the next play.
Farrow extended the lead to 25-15 on a 6-yard touchdown run with 10:21 remaining in the game. Ryan Jackson got the Cougars to the Tigers 18 on a 44-yard screen pass down the right sideline from O'Korn.
"It's kind of rough for us on the offense today," Farrow said. "It was grinding out all day. It was good to get in the end zone and put a touchdown on the board when we needed it."
After Derrick Matthews forced and recovered a fumble on Memphis' first drive, Houston covered 57 yards in six plays, capping the drive with a 17-yard touchdown pass to Daniel Spencer with 10:13 left in the first quarter to make it 7-0.
After Houston forced another Memphis turnover, Houston upped the lead to 10-6 on a 24-yard field goal by Richie Leone with 8:21 remaining in the second.
Memphis struggled to finish drives, taking three into the red zone, but they were unable to get into the end zone.
"Obviously, offensively you can't kick field goals every time you get the ball down there close," Memphis head coach Justin Fuente said. "You can't turn the ball over. Defensively, we can't make critical mistakes in the red zone. That pretty much sums it up."
Memphis, which lost its second-straight, continued to play well on defense, holding Houston's running game that had averaged 226.5 yards per game to just 38 yards and forcing the fourth turnover by Houston this season.
"It was really disappointing because we controlled the game, but we made a lot of mistakes," Memphis defensive end Martin Ifedi said. "(Houston) got turnovers away from us, and it put points on the board for them."
Houston's high-powered offense was held to just 84 yards in the first half and six first downs compared with Memphis' 200 yards and 10 first downs. Of Houston's 84 yards in the first half, 57 yards came on the Cougars' first drive.