Leinster’s defence of their Celtic League title is in tatters after they lost their fourth match on end – 18-23 to Scottish new boys Borders.
Leinster now have to win their final two matches, secure two bonus points and hope other results go their way if they are to make the quarter-finals.
Edinburgh thumped a poor Llanelli outfit 38-14, while Ulster ended Munster’s unbeaten run with a 26-17 victory at Ravenhill.
Scrum-half Neil Doak, an Ireland cricket international, scored all of Ulster’s points to add some spice to the Pool A table.
Neath all but confirmed a quarter-final berth with a comfortable 34-7 win over Ebbw Vale, thanks to a hat-trick of tries to fullback Gareth Morris.
Vale flanker Tyrone Morris must have broken a record when he was sin-binned 30 seconds after coming on as a replacement, in his first appearance since being red-carded against Caerphilly a fortnight ago.