Tries in the final few minutes in two of Saturday's First Trust Senior Cup quarter-final ties resulted in Ballynahinch eliminating City of Derry 33-29 and Belfast Harlequins overcoming Malone 33-28.
At Ballymacarn Park a depleted Hinch were taken all the way by an inspired Terry McMaster's Derry. The holders found themselves trailing 17-8 at the interval.
"After an hour we were 16 points in arrears but Derek Suffern made a few vital changes and we started to claw back the deficit," explained Director of Rugby Richard Hart.
"The difference in fitness told in the end."
Each team scored four tries with Craig Ternier, Robin Hart, James Simpson and Richard Reaney touching down for Hinch for Chris Quinn to convert two and kick three penalties.
Derry's Neil Burns had a penalty and three conversions to tries by Stephen Corr and David Graham who each scored twice.
Malone produced one of their best performances of the season as they led on two occasions but 20 points by Quins in the final quarter resulted in a narrow five point loss for last year's defeated finalists. In the other ties Ballymena, with five tries, were too strong for Banbridge 30-7 and Queen's defeated Rainey 25-24.
The semi-final draw will be made this evening.