We look at all the Friday action
Ulster made it 11 wins from a possible 11 in the Pro12 competition as they bounced back in style from last week's first loss of the season with a 27-19 win over Leinster.
A week on from their 9-10 home defeat to Northampton Saints in a European Cup match, Ulster ran in three tries to retain their unbeaten run in the Pro12.
And Springbok Ruan Pienaar again made a major contribution to his Irish province's cause - kicking three conversions and a penalty, apart from his contribution in general play.
* Meanwhile in a tense Welsh derby Aled Thomas' boot saw Scarlets claim the bragging rights against Cardiff Blues with a 9-6 victory - their sixth successive win against the region.
* In the other Friday encounter DTH van der Merwe's first-half double stopped Glasgow's recent Pro12 rot and condemned rivals Edinburgh to a morale-sapping 23-14 defeat at Scotstoun.
We look at all the Friday action!
Cardiff Blues 6-9 Scarlets
In a tense Welsh derby Aled Thomas' boot saw Scarlets claim the bragging rights against Cardiff Blues with a 9-6 victory - their sixth successive win against the region.
Flyhalf Thomas wasn't at his best, missing three kicks on a evening devoid of any real try-scoring chances, but held his nerve for the most part to sail over three attempts and secure the Scarlets' place behind Ulster in the Pro12 standings.
His opposite number Rhys Patchell did his best to keep the Blues within reach, but despite his two penalties they fell to their sixth defeat in seven games.
The Scarlets were dominating much of the early possession - they almost snatched a try from a charge-down after two minutes - but eventually settled for three points from the boot of Thomas on four minutes.
Thomas, whose last kick in the Pro12 got them a losing bonus point against Ulster, added another penalty on ten minutes after a powerful scrum from the visitors forced the Blues into conceding a penalty.
The hosts got themselves on the scoresheet five minutes later though, in their first stint in the Scarlets' territory they won a penalty and Patchell converted.
Set-pieces were proving scrappy for both sides, in particular line-outs which were thrown long and wayward on too many occasions during the middle of the half.
With chances few and far between Thomas' kick on the half hour, arguably his easiest of the night, took on extra significance but was skewed wide.
An excellent lineout drive from Cardiff moments later though almost brought its rewards, but when the ball came loose Patchell failed to release quickly enough to take advantage of the numbers out wide - and the flyhalf missed the resulting penalty.
Thomas, perhaps smarting from his earlier miss, made amends by kicking his next attempt a minute before the break which saw the Scarlets take a 9-3 lead at half-time.
The visitors came out strongest after the interval but a deliberate spell of pressure, lasting 16 phases, fizzled out to nothing but the Blues defence was being given a stern examination.
At the other end Patchell kicked the Blues within three points with his second penalty on 57 minutes before Thomas missed his attempted penalty ten minutes later.
Thomas then had the chance to set Liam Williams free with five minutes to go, but his pass was deemed forward and the fullback's try was ruled out.
And despite coming up short with a penalty in the final minute, Thomas and the Scarlets held on for their fifth victory in six Pro12 games.
For Cardiff Blues:
Pens: Patchell 2
Pens: Thomas 3
Cardiff Blues: 15 Jason Tovey, 14 Alex Cuthbert, 13 Gavin Evans, 12 Dafydd Hewitt, 11 Harry Robinson, 10 Rhys Patchell, 9 Lewis Jones, 8 Andries Pretorius (captain), 7 Sam Warburton, 6 Josh Navidi, 5 James Down, 4 Bradley Davies, 3 Scott Andrews, 2 Marc Breeze, 1 Taufa'ao Filise.
Replacements: 16 Rhys Williams, 17 Sam Hobbs, 18 Benoit Bourrust, 19 Macauley Cook, 20 Robin Copeland, 21 Alex Walker, 22 Ceri Sweeney, 23 Owen Williams.
Scarlets: 15 Liam Williams, 14 George North, 13 Jonathan Davies (captain), 12 Scott Williams, 11 Andy Fenby, 10 Aled Thomas, 9 Tavis Knoyle, 8 Kieran Murphy, 7 Aaron Shingler, 6 Josh Turnbull, 5 Johan Snyman, 4 George Earle, 3 Samson Lee, 2 Emyr Phillips, 1 Phil John.
Replacements: 16 Matthew Rees, 17 Rhodri Jones, 18 Deacon Manu, 19 Sione Timani, 20 Johnathan Edwards, 21 Gareth Davies, 22 Gareth Owen, 23 Gareth Maule.
Referee: Ian Davies (Wales)
Assistant Referees: James Jones, Sean Brickell (both Wales)
TMO: Gareth Simmonds (Wales)
Ulster 27-19 Leinster
Ulster made it 11 wins from a possible 11 in the Pro12 as they bounced back in style from last week's first loss of the season with a 27-19 win over Leinster.
A week on from their 9-10 home defeat to Northampton in the European Cup, Ulster ran in three tries, through Nick Williams, Andrew Trimble and a penalty score.
In response Leinster managed a late try from Fergus McFadden, with Ian Madigan scoring the rest of their points but Ulster's dominance in the scrum proved the difference between the sides.
Ulster had the better of the opening exchanges but could not take advantage, while Leinster were clinical with every opportunity.
Madigan knocked over two penalties in the opening quarter, both from wide on the right, to put his side into a 6-0 lead.
By comparison Paddy Jackson missed a couple of early shots at goal, but when it came to the third attempt, after 25 minutes, he made no mistake to reduce the deficit to three.
And on the back of a powerful Ulster scrum, Ruan Pienaar levelled the scores with a long-range penalty on the half-hour.
However Leinster hit back immediately through another Madigan penalty from straight in front when Iain Henderson was penalised for coming in at the side.
Leinster's ability to score with every chance they got was the reason they led but with three minutes left in the half Ulster took the lead for the first time.
The home pack was in complete control at the set-piece and when they earned a five-metre scrum another powerful drive from the Ulster eight left George Clancy with no choice but to give a penalty try, Pienaar converted to make it 13-9 at the break.
Leinster pulled three points back immediately after half-time when Darren Cave was penalised for not rolling away.
However Ulster responded with their second try of the game when Williams barged and twisted his way to just get the ball on to the line. Pienaar's conversion made it 20-12.
The home scrum remained dominant and on the hour mark it earned Ulster another penalty but Pienaar missed from the kicking tee for the first time.
Ulster looked in control but from a Leinster attack Rory Best was sent to the sin bin for failing to roll away, Madigan missing the ensuing penalty.
And despite being a man down it was Ulster who scored again. After some good work from the pack Pienaar produced an exquisite cross-kick for Trimble to collect and score the home side's third, the South African's conversion made it 27-12.
Leinster hit back with a try from replacement McFadden as the ball was spread wide by Madigan, who slotted the conversion to reduce the deficit to eight points.
However they could not find another score and ended up leaving Ravenhill empty-handed to lose their third consecutive game in all competitions.
Tries: Williams, Trimble, Penalty try
Cons: Pienaar 3
Pens: Pienaar, Jackson
Pens: Madigan 4
Yellow card: Rory Best (Ulster, 70)
Ulster: 15 Jared Payne, 14 Andrew Trimble, 13 Darren Cave, 12 Luke Marshall, 11 Craig Gilroy, 10 Paddy Jackson, 9 Ruan Pienaar, 8 Nick Williams, 7 Chris Henry (captain), 6 Robbie Diack, 5 Neil McComb, 4 Iain Henderson, 3 John Afoa, 2 Rory Best, 1 Tom Court.
Replacements: 16 Rob Herring, 17 Callum Black, 18 Adam Macklin, 19 Alan O'Connor, 20 Roger Wilson, 21 Paul Marshall, 22 Paddy Wallace, 23 Adam D'Arcy.
Leinster: 15 Noel Reid, 14 Andrew Conway, 13 Brendan Macken, 12 Gordon D'Arcy, 11 Fergus McFadden, 10 Ian Madigan, 9 Eoin Reddan, 8 Jamie Heaslip, 7 Sean O'Brien, 6 Kevin McLaughlin, 5 Devin Toner, 4 Leo Cullen (captain), 3 Michael Bent, 2 Sean Cronin, 1 Cian Healy.
Replacements: 16 Aaron Dundon, 17 Heinke van der Merwe, 18 Jamie Hagan, 19 Tom Denton, 20 Rhys Ruddock, 21 Isaac Boss, 22 Andrew Goodman, 23 Adam Byrne.
Referee: George Clancy (Ireland)
Assistant Referees: Peter Fitzgibbon, Olly Hodges (both IFRU)
TMO: Dermot Moloney (Ireland)
Glasgow Warriors 23-14 Edinburgh
DTH van der Merwe's first-half double stopped Glasgow's recent Pro12 rot and condemned rivals Edinburgh to a morale-sapping 23-14 defeat at Scotstoun.
The wing took his league tally to seven tries with a devastating first-half display which also saw Rob Harley cross for the hosts - ending their four-game Pro12 defeats.
But despite their dominance in the opening 40 minutes Glasgow's nerves in the second period were clear to see with Edinburgh going over through Piers Francis.
Glasgow made the brighter start and got their rewards as early as the sixth minute when Van der Merwe crossed in the corner.
The wing was the grateful receiver of Peter Murchie's well-timed pass and he went over unopposed.
Pete Horne was wayward with the conversion but eight minutes later it was the same left corner that saw Glasgow's second try, this time courtesy of Harley.
The back row was in acres of space after some relentless Warriors pressure to touch down and extend the hosts' lead to ten points - Horne's boot again letting him down from a tight angle.
Glasgow's superiority was further highlighted on 25 minutes when van der Merwe went in for his second try - again on the left hand side that had brought so much early joy for Warriors.
This time the flying wing had Nikola Matawalu to thank for a delightfully weighted kick and Horne also found his range with the boot, converting his first of the evening.
Greig Laidlaw got Edinburgh off the mark with a penalty just after the half hour and it seemed to galvanise the visitors into action.
The Gunners spent the rest of the half camped in Glasgow territory but couldn't make it count and went into the half-time break 17-3 adrift.
Laidlaw's second penalty of the evening five minutes after the restart reduced Edinburgh's arrears still further before Francis crossed for the visitors.
An incisive break from Matt Scott found the flyhalf who bundled his way over the line on 49 minutes - Laidlaw missed the conversion from out wide.
Duncan Weir slotted over a penalty for the Warriors to give them a bit of breathing space at 20-11, but Laidlaw kept his side in it with another three-pointer.
Not be outdone replacement Weir notched his second penalty of the evening and despite some late pressure from the visitors the Warriors held on and put one hand on the 1872 Cup.
For Glasgow Warriors:
Tries: Van der Merwe 2, Harley
Pens: Weir 2
Pens: Laidlaw 3
Glasgow: 15 Peter Murchie, 14 Sean Maitland, 13 Sean Lamont, 12 Peter Horne, 11 DTH van der Merwe, 10 Ruaridh Jackson, 9 Niko Matawalu, 8 Ryan Wilson, 7 Chris Fusaro, 6 Rob Harley, 5 Tim Swinson, 4 Al Kellock (captain), 3 Moray Low, 2 Pat Macarthur, 1 Ryan Grant.
Replacements: 16 Dougie Hall, 17 Gordon Reid, 18 German Araoz, 19 Jonny Gray, 20 James Eddie, 21 Henry Prygos, 22 Duncan Weir, 23 Stuart Hogg.
Edinburgh: 15 Greig Tonks, 14 Lee Jones/Dougie Fife, 13 James King, 12 Matt Scott, 11 Tim Visser, 10 Piers Francis, 9 Greig Laidlaw, 8 Stuart McInally, 7 Roddy Grant, 6 David Denton, 5 Izak van der Westhuizen, 4 Grant Gilchrist, 3 Willem Nel, 2 Ross Ford, 1 Allan Jacobsen.
Replacements: 16 Andy Titterrell, 17 John Yapp, 18 Geoff Cross, 19 Sean Cox, 20 Netani Talei, 21 Richie Rees, 22 Ben Atiga, 23 Dougie Fife.
Referee: Jerome Garces (France)
Assistant Referees: Andrew McMenemy, Bob Nevins (both SRU)
TMO: Jim Yuille (SRU)