Jenny Maguire's short-corner strike was all that separated Mount Anville and Loreto Foxrock in this South Dublin derby.
The powerful midfielder struck 13 minutes from time to earn a place in the quarter-finals of the Senior Cup, ending a spirited Foxrock challenge inspired by Sarah Greene, with third-year Molly Lamb pulling the strings in midfield.
Visitors Mount Anville had started the stronger. Aisling Naughton's pace caused serious problems and earned a quartet of first-half corners.
Foxrock weathered the early storm, though, with goalkeeper Mary Gilbride resolute and Ciara Williams pulling off a string of fine tackles.
And they responded in kind when Sorcha Conway's reverse-stick sweep drew the most telling save of the first half in the 27th minute, booted clear by Nicola Walsh to keep the tie locked at 0-0.
Foxrock continued to play some nice, controlled hockey, though the speed of Naughton and skills of Lisa McCarthy down the left meant there was always a clear and present danger.
But the hosts missed out on three corner occasions, and when Mount Anville earned their fifth setpiece, Maguire made no mistake.
Petra Kealy almost tied the game up with three minutes to go from Anna O'Grady's cross but she could not get enough on her effort and Mount Anville held on for a place in the last eight where they will play Muckross.
Elsewhere, Alexandra College's greater cutting edge saw them record a 3-0 win over Loreto Beaufort, Irish U18 international Deirdre Duke scoring twice in the last 10 minutes after Nicola Gray had smashed home a short corner on the stroke of half-time.
Mount Sackville had a more comfortable passage through to the last eight when they beat Holy Child of Killiney 6-1. They were ahead inside 50 seconds through Siun McLoughlin -- celebrating her 18th birthday -- and scarcely looked back.
Two corners before half-time made it 3-0 and they doubled their tally from play in the second half through Rachel Hinkson's brace and one from Olivia Smartt.
Mount Temple snuck past the challenge of Loreto Bray 2-1 with goals from Irish underage sprinter Sarah Murray and Jen Keating.
Our Lady's Templeogue were taken the distance by St Columba's but the Templeogue girls eventually prevailed 2-1 on penalty strokes.