Kidwelly and Newport Saracens both came agonisingly close to pulling off the surprise results of the fourth round only to eventually fall just short. No.8 Phil Middleton crashed over in the second half as Kidwelly, struggling in Division Two West, threatened to shock Division One outfit Builth Wells in mid-Wales.
Builth were twice reduced to 14 men as No8 Ben Duggen and prop Sean Hughes were shown yellow cards at Kidwelly rallied from a 5-3 half-time deficit and Leighton Walters added points with the boot. But cool-headed Rob Lloyd proved the difference as the Builth outside-half added to his first-half try by kicking two penalties to scrape a narrow 11-10 win.
Meanwhile Newport Saracens welcomed UWIC, sixth in Division One, and almost sent the students packing in a 60-point thriller. Chad Bushell, Phil Booth, Ross Madden and Matthew Woods all went over for Saracens who raced into a 19-7 half-time lead before two scores froom prop Jamie Stephens inspired a Uwic fightback. Centre Matthew McLean and wings Alex Eatly and Peter McKee grabbed the others as UWIC ran in five tries, four of which were converted by Tom Hancock in the 33-27 victory.
Division Three South-West leaders Tonna travelled to Llangennech with hopes of pulling off a surprise but found the Division One opposition too strong after wings Matthew Jacobs and Wayne Price scorched over for two tries each for a 34-7 home win.
In the only Division One match on Saturday, mid-table Waunarlwydd consignedYstrad Rhondda to the bottom of the League with a 14-11 victory.