Munster hero Ronan O'Gara's 20 points put a serious dent in Neath's Celtic League ambitions at the Gnoll tonight.
The Irish province proved too good in every department to run out 35-19 winners.
Neath were left to rue basic mistakes that handed the visitors two simple tries in the first half, which proved the difference in the end.
All Blacks coach Lyn Jones now has the task to get his side up for next weekend's difficult away trip to Edinburgh, where five points could sneak his side into a home quarter-final.
Fly-half Lee Jarvis kept Neath in touch with four penalty goals, but his side's reputation as the best defensive team in the competition took a battering as Munster ran in four tries.
In Galway, Connacht's unbeaten run in the Celtic League came to a crashing halt at the hands of Pontypridd.
The men from Pontypridd were in superb form, running out 40-0 winners against a side that had never been beaten by a Welsh team in the Celtic League.
Winger Gareth Wyatt scored a brace of tries and veteran fly-half Neil Jenkins chimed in with 12 points with the boot.
A late pair of tries to replacement back Matt Allen has put Cardiff into the Celtic League quarter-finals.
The Welsh capital beat Bridgend 37-12 at the Arms Park, and their bonus point for four tries puts them into the playoffs.
It was Cardiff's fourth win on end after a poor start to the season, while Bridgend crashed to their fourth consecutive loss after starting with wins over Newport and Borders.
Nicky Robinson (Cardiff) and Craig Warlow (Bridgend) each scored 12 points with the boot, but Cardiff's star-studded backline proved the difference on the day.
In contrast, the Ravens were clueless in attack and never looked like crossing the home try-line.
Edinburgh confirmed their place in the final eight with a 30-20 win over a gritty Ebbw Vale side, with talented scrum-half Mike Blair scoring a late try to give his team some breathing space.
The visitors to Eugene Cross trailed 10-13 at the break before British Lion backrower Simon Taylor and Blair scored crucial five-pointers.
And just when long-suffering Caerphilly fans thought their season couldn't get any worse, it did. Irish province Ulster left Virginia Park with a crushing 67-15 victory, with Ireland fly-half David Humphreys kicking 27 points.
WRU International Skills Coach Jason Strange is a busy man, combining the new role with that of Wales Under 20 attack coach, Ebbw Vale head coach and continuing to teach at Ebbw Fawr Learning Community.
Warren Gatland and Sam Warburton look ahead to this week's crunch RBS 6 Nations tie against France, where the Wales skipper in particular is keen to make his mark, as Paris has proved a bleak place for him in the past.
Following their historic win over England, Wales Under 20 suffered a narrow, 36-34 loss to their Scottish counterparts last weekend, despite outscoring them by five tries to three. Watch the match highlights and reaction.
WRU TV go behind the scenes with the Wales squad as they put the final touches in place ahead of the clash against Scotland at Murrayfield. Follow the squad on their captain's run, the kickers visit to Murrayfield and Neil Jenkins' press conference