The Islanders (2-1) rallied from an eight-point deficit, using a 10-2 run ignited by Ehab Amin's three-point play and 3-pointer to tie it at 46 with 7:19 left.
Rashawn Thomas made a layup and two free throws with Pye's go-ahead 3 in between, pushing their lead to four. The Islanders made 8 of their last 10 attempts from the line to ice the game.
The Billikens (2-1) were 21 of 51 overall and 11 of 21 on free throws. Achraf Yacoubou was the lone player in double figures for Saint Louis with 13 points.