Texas Tech was undefeated and ranked in the top 15. 1939 was the first Cotton Bowl appearance for Texas Tech. Sportswriters had tagged the California based Gaels as a "Cinderella" team due to their tawdry 5-2 record. and the Gaels entered with a 5-2-0 record.
Texas Tech committed 8 total turnovers in the game, including 5 interceptions and 3 fumbles. The Gales led the game 20-0 at the end of the third quarter on touchdown scores by Ed Heffernan and Michael Klotovich along with Whitey Smith's interception return for a touchdown. Texas Tech scored twice in the fourth quarter on touchdown catches by Elmer Tarbox and E. J. McKnight from Gene Barnett. The extra point on the second score was blocked, making it 20-13. Tech nearly tied the game when George Webb caught a pass from Barnett, heading for daylight. But Lou Rimassa stopped him in St. Mary's territory. But Tech could only get to St. Mary's 15 yard line as they failed to score, with St. Mary's holding on to win in one of the biggest upsets in college football history.
St. Mary's would only play in two more bowl games, losing both, and they later joining Division II football before disbanding in 2004. Texas Tech would not reach a Cotton Bowl again until 1995. The Red Raiders have never won a Cotton Bowl in their four appearances.