In the game between the teams ranked first and last in the Western Athletic Conference, the Bulldogs (20-3, 11-0) never trailed and led 14-2 after 7 minutes.
Louisiana Tech, which edged the Roadrunners 73-71 in their first game Jan. 12, led by 28 in the second half en route to continuing the fourth longest active winning streak in the nation.
Raheem Appleby and Jaron Johnson scored 10 each for Louisiana Tech, which has reached 20 wins faster than any time in its history. Of the 15 Bulldogs who played, 11 scored and 10 grabbed boards as the Bulldogs outrebounded Texas-San Antonio 53-37.
Kannon Burrage scored 15 to lead the Roadrunners (5-17, 1-11), who have lost four straight and 11 of 12.