Tied at 70 with 2:15 to go, Tyus got a steal and a bucket to put Omaha (6-5) back in front and sparked a final 7-2 spurt to cement the win.
Devin Patterson pumped in 17 points, Tre'Shawn Thurman had 14 and Mike Rostampour 12 for the Mavericks, who shot 45.8 percent from the floor to win their second straight. Tyus also grabbed a team-high nine rebounds.
UT-Pan American (5-7) rallied late in the second half to catch the Mavericks with a 12-2 run that included a 3-pointer from Shaquille Boga. But the Broncs went cold and the rally stalled.
Shaquille Hines led the Broncs with 27 points and five assists, while Boga finished with 18 points.