Pointer drove up the court after taking an inbounds pass, stopped on the left side and connected on a 17-footer, breaking a 61-61 tie and sending the Red Storm (17-15) into the second round.
Pointer finished with 15 points, seven rebounds and five assists.
Jakarr Simpson led fifth-seeded St. John's with 16 points and five boards.
The fourth-seeded Hawks (18-14) got 21 points from Carl Jones, and Langston Galloway added 16 and five boards.
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