At the other end of the table, bottom-placed Mumbles produced the second shock of the afternoon with an impressive 39-13 victory at home to mid-table Kidwelly. Not to be out-done, second-from-bottom Seven Sisters beat Pontyberem 31-11.
Champions-elect Penclawdd show no signs of taking their foot off the throat in Division 3 West, retaining their 17-point lead at the top of the table with a 54-26 hammering at fourth-placed Llanelli Wanderers. Hendy are resigned to finishing last after their 65-0 hiding at home to Aberystwyth.
Tonna players and officials owe rivals Nantyffyllon a few beers as they put one hand on the Division 3 South-West title on Saturday.
Leaders Tonna sneaked past Cwmavon 11-7, and now have a three-point advantage and two games in hand over Vardre, who lost 23-22 in a nail-biter at Nantyffyllon.
Pontarddulais have been handed the Division 4 West title on a plate without even playing a match. With two games to play, the leaders have an unbeatable lead after nearest challengers Ammanford stumbled 28-26 at Llandeilo.
Heol y Cyw's 15-3 win over nearest challengers Birchgrove looks to have given them the Division 4 South-West title, although third-placed Glynneath are still mathematically in the race. They need to win their remaining four matches, and hope that Heol y Cyw lose their remaining four.
Llanybydder are making a late charge in Division 5 West, with their 77-6 mauling of Bynea looking even better after leaders Burry Port lost 29-17 at Gowerton, while BP Llandarcy are making things interesting in Division 5 South-West.
Llandarcy beat Pyle 49-15 to join Glyncorrwg at the top of the table, and they have a game in hand after Glyncorrwg's 19-17 loss at Porthcawl.