The Duddingston side won 8 and 7 over the double foursome and now take on Watsonians, who sqeezed past Hailes at the 19th hole.
Third-round results: Watsonian bt Hailes at 19th; Temple bt Royal Bank 8 and 7; Buckstone Golf Club bt Lochcraig 5 and 4; George Heriot's FP lost to Caermount 9 and 8; Thorntree bt Dunbar Castle 5 and 4; Edinburgh City Chambers bt Kingston 8 and 7; Cramond bt Corstorphine 8.30 one hole; Lothian & Borders Police lost to Ethicon 5 and 4.