The Pro14 Grand Final is a date every Welsh, Scottish and Irish rugby fan has marked in their calendar.

Since the introduction of a playoff system in 2001, returning again in 2010 after a brief hiatus, the competition has thrown up a series of classics in the winner takes all game.

Although hard to pick favourites (sorry to Glasgow Warriors and their phenomenal victory in 2015) The Flanker has ranked the five best finals in its young history, both in terms of the match itself and its significance.

5.) 2001: Leinster 24 - 20 Munster

Straight off the bat is the competition’s first ever final, back in 2001 when it was known as the Celtic League and had no Italian representatives.

A much shorter competition that finished in December, it was still a classic match up as the two old rivals squared off in a rickety Lansdowne Road.

Both sides had topped their respective pools and while Leinster cruised past Newport and Glasgow with ease in the playoffs, Munster were pushed all the way and just squeaked past Llanelli and Ulster.

In the final, Leinster had to play the majority of the game with 14 men after British and Irish Lions flanker Eric Miller was sent off in the 25th minute for kicking Munster centre John Kelly in a….errrmmm…delicate area.

Before that, the late great Anthony Foley barged over the line for Ronan O'Gara to convert and put Munster 7-0 in front.

Nathan Spooner responded with two penalties for Leinster while the Munster scrum-half Mike Prendergast was sin-binned, with John O'Neill's try in the corner putting Munster 12-6 clear at the break.

Gordon D'Arcy touched down after half-time to put Leinster in front and with 10 minutes to go, Shane Horgan scored a brilliant try after a genius Brian O’Driscoll break and chip ahead, sealing the title for the Dubliners after a monumental defensive effort.

Opposite winger and namesake Anthony Horgan grabbed an injury-time try for Munster, but Leinster did enough to hold on for their maiden Celtic League championship.

4.) 2017: Munster 22 - 46 Scarlets

This was the second league triumph for the Llanelli-based team, following on from their 2003/04 Celtic League win which was the season that saw introduction of the provincial system still used today by the WRU.

In 2016/17, it was a vintage Scarlets team that hammered Munster at the Aviva Stadium in Dublin after they came third in the regular season Pro 12 table, the season before the Cheetahs and the Southern Kings rounded up the league to 14.

Led by inspirational Scotland captain John Barclay, they started like a house on fire with Liam Williams gathering through a chip ahead to dot down after nine minutes.

Scarlets were not afraid to run the ball from deep, with Jonathan Davies creating a try from his own 22 on the 20 minute mark.

After breaking up field, he made a series of exchanges with the league’s top try scorer that season, Steff Evans (to you, to me, to you), who eventually dived over to send the Llanelli faithful into raptures.

The carnage didn’t end there as Scott Williams made a darting break and passed back inside to Gareth Davies (which looked forward on replay but was allowed) who scampered under the posts.

Munster looked out on their feet, hit by a relentless red wave of shirts that buzzed around Rassie Erasmus’ team. Wayne Pivac, then Scarlets coach, had clearly instructed his team to let the handbrake off and attack the Irish province in the wide channels, which they did to devastating effect all game.

On 30 minutes, the fat lady was clearing her throat as Tagdh Beirne barrelled over to make it 29–10 at half time, after a Tyler Bleyendaal try gave Munster a sniff, a lead that not even Northampton Saints could surely squander.

They didn’t release their grip on the game and the title and despite a barmy last 10 minutes which saw four tries scored, two apiece, the Welsh side claimed a much-deserved victory.

3.) 2016: Connacht 20 - 10 Leinster

Not an absolute barn burner by any stretch of the imagination, but the fact the Galwaymen upset the odds and convincingly dethroned rugby royalty in Leinster places the 2016 Pro12 Grand Final high on our list.

These two sides actually finished level on 73 points each after 22 games played, only separated by virtue of points difference.

Leinster breezed past Ulster in their semi 30-18 while Connacht were pushed hard by Glasgow, as a full time score of 16-11 shows, to reach their only Grand Final to date.

Led by the brilliant Pat Lam as Director of Rugby, this Connacht side contained now household names like AJ MacGinty, Ultan Dillane, Bundee Aki, Robbie Henshaw, Kieran Marmion and John Cooney.

Irish international Tiernan O'Halloran, a classy operator at fullback, got them off to a great start at a sunny Murrayfield with a cheeky show and go that left opposite number Rob Kearney grasping at thin air.

Much like Lam’s Bristol like to run the ball from anywhere in the present, his 2016 Connacht were no different as they were constantly looking to attack open space, create mismatches across the field and offload at every opportunity.

Pacy winger Niyi Adeolokun crossed the whitewash for Connacht on 22 minutes after he chipped ahead and then VOLLEYED the ball as it dropped out the sky (yes that’s right, volleyed) on to gather and dot down to give his side a cherished 12-0 lead.

After the break, the Galway boys kept their pedal to the floor, smothering the Dubliners with their intensity and expansive play. On 56 minutes, MacGinty chipped through for winger Matt Healy to gather and slide over to make it 20-3.

Just when you thought they could start putting green and white ribbons on the trophy, Sean Cronin responded for Leinster to make it a nervy finish but the underdogs held on.

In the same year as Leicester City won the Premier League, Connacht performed their own miracle. As Miles Harrison put it on commentary: “In a season of sporting fairytales, you can put their name on the list.”

2.) 2018: Leinster 40 - 32 Scarlets

Did I mention the Scarlets under Wayne Pivac were a classy team?

In the year South African franchises were added to the competition, the Llanelli outfit were aiming to emulate what their opponents had already done and successfully defend their crown in back to back years.

In their way stood Champions Cup winners Leinster, who just two weeks before had ground their way to their European title via a narrow 15-12 win against Racing 92.

Would they be jaded and tired following their continental exertions? Absolutely not. Both teams went hammer and tong at each other before Leinster’s quality ground down the plucky Welsh side.

Jonny Sexton and Leigh Halfpenny swapped early penalties before the game sparked into life when big Devin Toner stretched his long levers to score the first try in the 29th minute.

Scarlets wing Johnny McNicholl blasted over from short range to nudge his team to within three points before quick hands in coffin corner allowed Kiwi James Lowe to diver over for Leinster; a hammer blow to the Welsh side as they trailed 21-11 at the break.

After half time, Sean Cronin and Jordan Lamour’s quickfire scores looked to have put the game to bed at 33-11 but McNicholl finished wonderfully in the corner to keep Scarlets hanging on to the coat tails of the Dubliners.

Joey Carberry’s lovely break and inside ball to Jack Conan was a dagger through the hearts of their opponents as Leinster stretched into a 40-18 lead.

Surely all done and dusted? Not quite. Werner Kruger, the South African tighthead, bashed over but it would prove to be too little too late, despite a quite brilliant coast-to-coast try finished off by McNicholl again after a stunning 80m break by Scott Williams that made the scoreline a more respectable 40-32.

It capped a remarkable 2018 for Irish rugby, with a Six Nations Grand Slam, a Champions Cup and now a Pro14 title all safely in the trophy cabinet in Dublin and cemented Leinster’s place as the dominant club side in Celtic rugby.

1.) 2012: Leinster 30 - 31 Ospreys

Tries, late scores and an underdog victory - what more could you possibly ask for from a Grand Final? This was arguably the best Ospreys team in their 17 year history and they delivered in the bear pit of the RDS.

Equally as impressive was the Swansea side dispatching Munster in the semi-final 45–10, running in five tries in the process and coming second in the regular season table.

It was a team with a formidable pack, with Paul James, Richard Hibbard, Adam Jones, Alun Wyn Jones (capt), Ian Evans, Ryan Jones, Justin Tipuric and Joe Bearman starting the final, with wing wizard Shane Williams leaving for Japan at the end of the season.

Leinster were in the middle of a run which saw them make five consecutive finals, with some of their veterans like Brian O’Driscoll, Gordon D’Arcy, Mike Ross and Leo Cullen still able to bring big performances on the biggest stages.

Jonny Sexton and Dan Biggar traded early penalties before Sean Cronin cut a fine line to crash over for the opening try.

Ospreys were hit by a sucker punch as Isa Nacewa gathered his own team’s kickoff and jogged in for an easy score, to leave the Welsh team an uphill climb as they trudged in for the oranges 17-9 down.

However, they roared out the traps after the break, crucially an extra man to the good as referee Poite had sin-binned loose-head Heinke van der Merwe before halftime for scrum infringement.

Richard Fussell made a break down the right and although the full-back was hauled down, Beck picked a great diagonal line to crash over with Biggar's conversion bringing ought Ospreys within a point.

A brace of Sexton penalties nudged Leinster further ahead before the man of the hour Shane Williams squeezed in at the corner to make a seesaw game 23-21 with 20 minutes left.

When Isa Nacewa turned and stretched past defenders on his way to scoring for the Dubliners, it felt like curtains for Ospreys as they were left chasing the game at 30-21 down.

A Biggar penalty on 73 minutes set up a grandstand finish, with prop Nathan White becoming the second Leinster prop to be sin-binned as the Welsh side chased a famous victory.

Cometh the hour, cometh the man. With Leinster hanging on for dear life defending their line, the ball was spun out to the dimunitive dynamo Shane Williams.

Like he has done thousands of times previously, he dummied, shimmied, and twisted like an eel to dot down and give Biggar a kick on the angle to win the Pro12.

The iceman banged it straight down the middle, cue wild celebrations and what must have been a good night down Grafton Street for the Swansea boys.

On the final whistle, Shane WIlliams summed up the occasion superbly, telling the Guardian: "I have had a blast but it is time to do something else now.

"I have had a lot of fun and will miss it, but to go out with a trophy was everything I could ask.”