John Mulvihill accepts that 80 minutes of rugby will deliver a rightful verdict on his Cardiff Blues side when they face the Ospreys on Judgement Day.

The Blues head coach has overseen a strangely inconsistent campaign, during which the region have recovered from a poor start, hit some admirable heights in mid-season, and then faded away again in recent weeks with defeats to Munster and Connacht.

All of which makes a shoot-out against the resurgent Ospreys – for a play-off stab at qualification for the Heineken Champions Cup – a suitable finale.

Mulvihill thinks either his team or the Ospreys will deserve whatever comes their way at their final whistle.

“It’s a winner-takes-all, so whoever wins this game will finish fourth in the pool and will probably be the best Welsh region across the calendar year,” says the Australian.

“It’s a game of massive significance for us, after tasting Heineken Champions Cup rugby this year, and we want to go back and player there again next year.

“We need to improve from the last time we faced Ospreys where they won down at Liberty Stadium.

“If we want to be the best performing Welsh region this year, we need to win this weekend.

“Winning is all we’ve been thinking about in our preparations, and it’s been going really well for us.

“The roof will be closed, the conditions will be nice and quick and hopefully our in-form guys out wide will find some space out there.”

There is nothing better than a local spat to get the juices flowing. And that’s exactly what Judgement Day has done for Welsh regional rugby ever since it began at the Principality Stadium in 2013.

The appetite for the regional battles has grown every year and is now viewed as one of the highlights of the Welsh rugby calendar. There is so much at stake, and this year is no exception.

For those who aren’t fully clued up about what can happen this weekend, then here is a rough guide to the possible permutations:

• The top three teams in each Conference will go through to the Knock-Out stage of the competition and qualify automatically for the Heineken Champions Cup next season.
• The two next highest placed non-South African teams will then meet in a play-off match for the seventh and final place in the Heineken Champions Cup. The team with the most points in the regular season will have home advantage.
• In Conference A, three teams have already qualified for the Knock-Out stage – Glasgow Warriors, Munster and Connacht. That leaves the Ospreys, in fourth (54 pts), and Cardiff Blues, in fifth (53 pts), battling it out to reach the European play-off place.
• In Conference B, reigning champions Leinster are already guaranteed a home semi-final having topped their table. Ulster can’t be caught in second, but the third place is still live between Benetton Rugby (52 pts), Edinburgh (51 pts) and Scarlets (50 pts).

This weekend Scarlets meet Dragons in Judgement Day (3.00pm), Benetton go to Zebre (3.00pm) and Edinburgh head to Glasgow (7.35pm). It means the Scarlets could yet creep into the play-offs if other results go their way.

The Scarlets can also reach the European play-off to face either Ospreys or Blues. They have played in the top-tier of European club rugby in every season since they entered in 1996.

However, if Benetton and Edinburgh win with a bonus-point the Scarlets will be condemned to European Challenge Cup rugby for the first time in their history with a sixth place finish.

Guinness PRO14 Knock-Out Stage

Quarter Finals (as things stand)

Match 1: Conf A 2 (Munster) v Conf B 3 (Benetton)

Match 2: Conf B 2 (Ulster) v Conf A 3 (Connacht)

Semi-Finals (as things stand)

Conf A 1(Glasgow Warriors) v Winners Match 2

Con B 1 (Leinster) v Winners Match 1

Final

Celtic Park, Glasgow – 25 May

For the Scarlets, Guinness PRO14 champions two years ago and beaten finalists last season, it is going to be last chance saloon in trying to creep into the Knock-Out phase.

They still needs a few favours on the last day of the regular season, but they will need to keep their pedal to the metal throughout the game against the Dragons to give themselves any chance of giving new Wales head coach Wayne Pivac and his assistant Stephen Jones a meaningful send-off.

It hasn’t been the greatest of seasons for the outstanding Welsh region of recent years – they also reached the semi-finals of the Heineken Champions Cup last season – but no team is going to relish facing them in a play-off situation with something on the line at the end of the season if they can make the top three or four.

Their record on Judgement Day is also very good, with five wins over the Dragons and one reverse against the Blues. Only the Ospreys, with four wins over the Blues a fifth against the Dragons and one defeat to the Blues in 2017, can match that record.

The battle between the Blues and Ospreys is going to be another ‘must-win’ occasion for both sides. Whoever comes out on top will reach the European Play-off and the other incentive is to clinch a home game in that game.

The team with the most points gets the home draw and both Welsh regions are ahead of their rivals on the other side of the draw coming into the final round (Conf A: Ospreys 54, Blues 53; Conf B: Benetton 52, Edinburgh 51, Scarlets 50).

You have to go back to Judgement Day 2017 for the last time the Blues beat the Ospreys. This season it was 20-11 to the Swansea-based region at the Liberty Stadium on 5 January and they completed a hat-trick last winter.

They won an Anglo-Welsh Cup tie at the Arms Park 26-16 and then came out on top at home 20-11 in the PRO14 and were 26-23 winners at last year’s Judgement Day contest.

The Blues will come into the contest on the back of successive defeats to Irish sides Munster and Connacht, while the Ospreys have picked up of late with three bonus-point victories in a row over Dragons (29-20), Cheetahs (31-14) and Southern Kings (43-7).

One man who will be looking forward to playing on the big stage once again will be Ospreys full back Dan Evans, who notched a hat-trick in the seven try win over the Kings. That took him to 10 for the season and 45 overall in 182 appearances in the PRO14.

He has featured for three of the four regions – Scarlets, Dragons, Ospreys – on Judgement Day and has scored more tries than anyone else (3).

Adding extra spice to the Blues v Ospreys clash will be the recent announcement that Wales Grand Slam outside half Gareth Anscombe will be switching regions at the end of the season. One final hurrah with the Blues wouldn’t go amiss as far as his team mates and fans are concerned.