The Spartans (11-2) got the winning touchdown after Marcus Rush blocked a Baylor field goal with just more than a minute left.
When No. 4 Baylor (11-2) got the ball back for one last try, Bryce Petty was sacked on consecutive plays before Riley Bullough’s clinching interception.
Petty completed 36 of 51 passes for a Cotton Bowl-record 550 yards and three touchdowns, two to speedy freshman KD Cannon and the other to 390-pount backup guard LaQuan McGowan that put Baylor up 41-21 late in the third quarter.
Jeremy Langford ran for 162 yards and three touchdowns for the Spartans, whose only losses were to playoff teams Oregon and Ohio State.
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