UCD Marian stunned Neptune to set up a play-off semi-final date away to DCU Saints, while UL Eagles will take on UCC Demons in a repeat of the 2012 National Cup final after their win away to Killester.
UCD weren't expected to cause Neptune too many problems, but they produced their finest display of the season as Owen McNally got 23 points in the 83-80 win.
UL Eagles are still on course for the double after an 87-71 win away to reigning champions Killester. Victory would have been particularly pleasing to Eagles head coach Mark Keenan, who left the capital giants last summer.
In the Women's SuperLeague quarter-finals, Waterford Wildcats beat 11890 Killester in overtime to set up a semi-final clash with UL, while DCU Mercy will take on old foes Glanmire after their win over Meteors.