Hill carried the ball 17 times, scoring three rushing touchdowns, and went 9-for-26 passing with an interception for the Cougars (1-1), who broke a school record with 550 total rushing yards.
Jamaal Williams also provided a potent ground attack, compiling 182 yards on 30 carries, and Paul Lasike added 87 yards with a score on 15 attempts in a game whose start was delayed by strong thunderstorms across Provo.
Justin Sorensen booted four field goals in Brigham Young's win.
The Longhorns (1-1) fell as David Ash was held to 19-for-33 passing efficiency for 251 yards and two touchdowns before leaving with an injury in the fourth quarter.
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