The combined point total of 140 breaks the previous record of 137, which came in 2016 when Pittsburgh defeated Syracuse, 76-61.
SMU and Houston fell six points shy of the single game record (including overtime), which occurred in 2018 when Texas A&M (74) and LSU (72) played seven overtimes.
The record-breaking score came with three minutes, 37 seconds left in the game when Houston's Stacy Sneed scored on a 52-yard run.
SMU and Houston traded touchdowns for the first seven possessions of the game and the Mustangs led 56-35 at halftime. That first-half total (91 points) was three points off the single-half record set by Navy and North Texas in 2007.
Mordecai's nine touchdown passes combined with seven from Houston's Clayton Tune also set a new single-game FBS record for touchdown passes (16). The previous record came in 2014 when Western Kentucky's Brandon Doughty (8) and Marshall's Rakeem Cato combined for 15.