Malek Green added 13 points and 11 rebounds for the Eagles (4-8).
IUPUI tied the game for the final time on an Evan Hall dunk with two minutes left but then went 1 of 8, including six misses from the arc. Walker drove through the middle for a bucket for the lead, A.J. Hicks made a steal that Green turned into a basket on a baseline drive as the shot clock was winding down and Walker added two free throws with seven seconds left.
IUPUI trailed by 15 before closing the final 7 1/2 minutes of the first half by outscoring Morehead State 21-5, finishing with a dunk by Elyjah Goss at the buzzer to lead 37-36.
Camron Justice scored 20 points, his ninth game this season of at least 20 for IUPUI (8-5).
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