John Mulvihill’s true impact on Cardiff Blues this season will be put to the test at the Liberty Stadium on Saturday when his side looks to beat the Ospreys in Swansea for the first time since 22 December, 2005. Thanks to their back-to-back regional derby triumphs over the Dragons and Scarlets, the European Challenge Cup holders will head west once again at the weekend chasing an impressive hat-trick of derby wins in the space of 16 days.

Cardiff Blues stunned the Scarlets 43-5 in the West v East derby at Parc y Scarlets. Here, Dai Sport’s Harri Morgan analyses how Blues coach John Mulvihill got his tactics spot-on. Martyn Williams use of the rope a dope analogy in commentary on the East versus West derby at Parc Y Scarlets, was just about spot on.

John Mulvihill praised his Cardiff Blues for baiting the trap he insisted the Scarlets had fallen into after becoming the first team to win in Llanelli in the Guinness Pro 14 for over two years. It was a dominant, bullying 34-5 victory for the Blues on Saturday evening who were happy to let the Scarlets have plenty of ball, knowing they could do little with it other than hand over possession. A brace of tries from Ray Lee-lo plus a try apiece from Gareth Anscombe and Lloyd Williams was enough to see off Wayne Pivac’s side. All the Scarlet could muster was a first-half score from Johnny McNicholl.

Jonathan Davies has told his Scarlets teammates they need to be bold if they are to save their season in 2019. The Wales centre has urged the region to return to the swashbuckling style of a year ago when they host the Cardiff Blues on Saturday evening. Davies admits the Scarlets have been found wanting in recent weeks with seven defeats in their last nine matches, including four on the trot going into the latest Welsh derby.

Wayne Pivac has admitted his Scarlets team owe it to their fans to prevent a blip growing into a crisis. The Wales coach-elect has challenged his players to respond when they host the Cardiff Blues in Saturday’s Welsh derby following a four-game losing sequence. The region have seen their European dreams disintegrate in recent weeks and their Guinness Pro 14 ambitions also took a blow – not to mention their local pride – when they were beaten by the Ospreys just before Christmas.

So, how were the first Welsh festive derbies for you? Full of good cheer? A winter warmer to give you a glow right through to the Six Nations? Harri Morgan watched the Ospreys do battle with the Scarlets and was left wondering whether he should have gone shopping instead. As the game got underway at the Liberty, yesterday, I struggled to reconcile the vast number of empty seats with the occasion – or at least my own perception of the occasion. Ok, it wasn’t Boxing Day, but this was, nonetheless the West Wales Christmas derby – not quite the Catalina Wine Mixer of Welsh Rugby days – but it’s up there. The festive games have come to be the last bastion of the rivalries that once were, or at least so I am told.

Luke Morgan insists he has no regrets he spent so long in Sevens rugby – even though he’s ripping it up in the full form of the game. Morgan added to his growing reputation with a true predator’s match-winning try for the Ospreys in their festive derby victory over the Scarlets on Saturday. The 26-year-old – who made his Wales debut against Scotland last month – outpaced Tom Prydie to touch down for the only try of the game as the home side claimed a 19-12 victory at the Liberty Stadium.

Ken Owens believes it will be trial by television when the Scarlets go to the Liberty Stadium for the second of the Welsh festive derbies on Saturday. The trial in this sense is one for Warren Gatland’s national selection with the Scarlets hooker suggesting Wales places could be won and lost depending on performances between the old rivals. Owens’ side may have won their last 10 derbies, including their last visit to the Ospreys, but this game has a far more open feel to it than in recent years. And given the announcement earlier in the week that Stephen Jones will be joining Wayne Pivac in the new Welsh coaching team next year, it will have an extra edge.

The hottest ticket in town will soon be Wales v England in the Six Nations. But what about the regions? How warm are those seats? Not heated by enough bums on them, according to Peter Jackson of The Rugby Paper, who has compared the numbers watching Wales’ favourite rugby team with those who supply all their players. A startling fact can be unearthed from the mound of attendance figures at the Millennium Stadium last month – that more than 36,000 fans support Wales at the expense of their regional teams.

Welsh interest in the Heineken Champions Cup – in terms of the knockout stages, at least – is already over. It contrasts sharply with the success of Wales in the autumn, so as we head towards the Six Nations, Geraint Powell tries to unravel the contradiction. It is always difficult to dispassionately analyse a Welsh autumn internationals campaign in the immediate aftermath, for the mood in Welsh rugby nowadays only ever veers wildly between “world beaters” or “the end of the world is nigh”. The story of the Warren Gatland era has been of disappointment in the November friendlies, relative to the Welsh performances in the tournament rugby of the Six Nations and the World Cup.

Wayne Pivac has offered no excuses after the Scarlets lost for the third successive time in the Heineken Champions Cup to end any realistic hopes of making the knockout stages. A narrow 25-24 home defeat to Ulster on Friday night means the region are still without a win at the halfway mark of the pool stages. The Scarlets needed a victory if they were going to repeat last season’s sequence of two early defeats ushering in four straight victories, but it never looked likely.

It’s crunch time in Europe, so Robin Davey looks at the big questions. Do the Scarlets have a backstop position against Ulster even though Leigh Halfpenny is injured? Can the Cardiff Blues avoid a very hard border crossing when they go to Saracens? And what was the advice from the WRU given to the Dragons before they published their teamsheet? Europe is back on the rugby agenda and though it’s only the second block of the pool stages at least one Welsh region is in danger of crashing out without a deal. Last minute soundings are being taken with some final persuading to be done as the Scarlets count down to the crucial Champions Cup vote tonight.