The Red Raiders enjoyed balance on offense, with seven players scoring at least eight points. Darko Cohadarevic collected a game-high 13 rebounds.
Tairu was 6 of 10 from the floor, including two 3-pointers.
Texas Tech (1-0) led 42-21 at halftime, and a 20-0 run during the first 6 minutes of the second half gave the Red Raiders a 64-25 cushion.
Tyler Cain led South Dakota (0-1) with 11 points and nine rebounds.