Hameed Ali scored 13 points and tied a career high with nine assist for TAMU-CC (12-3, 3-0 Southland Conference), which has won five in a row and 11 of its last 12. Ehab Amin added 12 points and matched his career best with five steals.
Texas A&M-Corpus Christi jumped out to an 18-3 lead just more than six minutes in, but Lamar tied it at 39 going into halftime.
The second half featured 18 lead changes, the last of which came when Rashawn Thomas made a pair at the line with 4:39 left to put the Islanders up 75-74. Thomas' free throws came during an 11-1 run - during which he hit 7 of 8 foul shots - that made it 84-76 with 2:09 remaining and the Islanders held on from there.
Garth led Lamar (9-7, 1-3) with a career-high 25 points.