The Lions (5-12, 2-2 Southland) exploded in the second extra frame, outscoring Incarnate Word 18-8, as Jackson went for eight points in the session.
Filmore forced overtime with a 3-pointer with three seconds left in regulation. Denzel Livingston's 3-pointer tied it at 90 with 1:29 left in the first overtime and both Livingston and Jackson missed 3s in the final 30 seconds to prompt the second OT.
Incarnate Word (9-5, 1-3 Southland) used a 13-2 run at the end of the first half to build a 44-40 advantage at the break.
DeVonte Upson had 19 points and 12 boards for the Lions, while Onochie Ochie added 15 points.
Livingston finished with 27 points and Kyle Hittle had 21 for the Cardinals.