Muema had 105 yards on 14 attempts, and Katz was 16 of 22 passing for 181 yards for the Aztecs (4-3, 2-1 Mountain West), who were not penalized in a game for the first time since 1973.
Conner Smith was 18 of 22 for 165 yards and an interception for the Rams (1-6, 0-3).
SDSU converted all three of Colorado State's turnovers into touchdowns, and scored another TD after the Rams gave the ball up on downs.
On the first play from scrimmage in the second half, Marquise Law fumbled for Colorado State, and Jake Fely recovered for the Aztecs. Two plays later, Katz scrambled to the end zone from 11 yards out to give SDSU a 24-7 lead.
Largent had two interceptions and Fely two sacks for the Aztecs, who have won seven of the last eight meetings between the teams.
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Ohio State quarterback Cardale Jones was taken to a hospital Wednesday night and treated for a severe headache, according to multiple media reports.
The Florida Gators will start Treon Harris at quarterback in Saturday's opener vs. New Mexico State over redshirt freshman Will Grier, coach Jim McElwain said Tuesday.
Baylor University has hired a Philadelphia law firm to independently investigate the university's handling of sexual assault complaints, including one against defensive end Sam Ukwuachu.
Oregon State and former coach Mike Riley face a federal Title IX lawsuit filed by a woman who said she was raped as a result of the coach's failure to correct a sexually violent culture.
James Madison players will wear decals on their helmets during Saturday's season-opening game in memory of the two journalists who were killed during a live television broadcast.
Los Angeles prosecutors have charged a man in connection with the theft of the University of Southern California's copy of O.J. Simpson's Heisman Trophy more than 20 years ago.