Trainer Evan Williams, jockey Donal Fahy and Plunkett enjoy a Ffos Las first
Ffos Las took its place as a working racecourse on Thursday, showing every sign that the new kid on the block will hold its own among the grown-ups.
The pomp and circumstance of Royal Ascot, with Ladies' Day and the Gold Cup on the menu, may have held the racing world's gaze for a while that afternoon.
But as the sun began to dip, way at the other end of the M4 and beyond to Trimsaran, a 10,000-strong crowd showed that there is also a huge appetite for top-class racing in a new outpost of the sport.
It means an awful lot as a Welshman to come here and get the first winner
Plunkett's trainer Evan Williams
Ffos Las, constructed on the site of an open cast coal mine, is the first turf racecourse to be built in Britain for more than 80 years.
At 1pm sharp the gates were opened for the first time, with the crowd swelling swiftly despite the first of the seven-race jump meeting not scheduled to begin until 6.20.
Many of the arriving spectators bore comparison with the finery of Ascot displayed on the big video screens, although the afternoon was not quite as warm as some of the ladies would have wished in their outfits.
But a covering of cloud and the occasional chill gust of wind - somehow clear blue skies would have seemed improper for the start of this west Wales venture - was never going to spoil the sunny outlook of those assembled.
One man beaming from ear-to-ear was Wales dual-code rugby great Jonathan Davies, who opened the grandstand named in his honour.
"It's a big event and the facilities are just unbelievable. I worked on the site as a labourer when it was just a big hole in the ground," said Davies.
Rugby great Jonathan Davies shares his thoughts with BBC Sport Wales
"It's unbelievable that 25 years on I'm back here - it's a fantastic racecourse."
The throng and the excitement built steadily as the first race approached and this urgency translated itself to the jockeys and the horses.
Tubby Nugget, one of the outsiders, was particularly skittish as she was led around the enclosure, giving the plastic safety barriers a thorough test with a bucking rump.
All this took place to the background of Welsh tenor Wynne Evans marking an historic beginning by belting out the Welsh national anthem, Hen Wlad Fy Nhadau - ably accompanied by several thousand voices.
As the jockeys mounted and made their way out on to the course, the crowd streamed after them and took up station in deep rows overlooking the home straight.
The bookies had done brisk business and Dai Walters, the man responsible for the racecourse's existence, had seen his first horse of the night - Ffos Las Diamond, ridden by Tony McCoy - backed in to as low as 10-11.
This had eased to 6-4 by the start of the Freebets.co.uk 'National Hunt' Novices' Hurdle, but still left Ffos Las Diamond as favourite.
However, as the field entered the home straight it became clear that there was going to be no fairytale start - on the track at least - for Walters, who finished the evening without a winner.
Instead it was Plunkett who reached the finishing post first, the 15-8 shot ensuring that jockey Donal Fahy shared the honour of being the first names entered in the winners' ledger at Ffos Las.
Spectators gathered early to enjoy the Ffos Las festivities
The home support could take solace that Plunkett is trained by Welshman Evan Williams.
"It's great to have a winner here, first day, first race... great crowd, great track," said Irishman Fahy.
"He [Williams] is my boss, he's been absolutely tremendous to me since I started with him, he's given me loads of opportunities and it's just brilliant - lovely to ride the first winner here for him."
Williams was delighted to make his mark at Ffos Las so early, even if it was at the expense of Walters' hopes.
"That's racing, I know everyone is here to enjoy themselves but at the end of the day it's business to us lads and there's no such thing as giving people a free ride in this job," Williams said.
"But it is brilliant, it means an awful lot as a Welshman to come here and get the first winner but we've got to get up in the morning and go and do it elsewhere, so it's important to keep a level head about it all.
"It [Ffos Las] is an excellent job - I would say that - but they've done an excellent job.
"It's a credit to everyone concerned, it's just nice that everybody is getting behind it, this is what we need, something positive, not negative all the time"
Another 15-8 shot, Turf War, took the second of the night - the Castell Howell Novices' Hurdle.
But that race saw an unwanted first for Venir Rouge who became the first faller at Ffos Las, leaving jockey Wayne Hutchinson with the red face.
McCoy might not have been able to start the night with a bang on Ffos Las Diamond, but the jockey showed his champion credentials as the evening progressed to record a fine treble of wins.
The third race saw McCoy lead the Jonjo O'Neill-trained Sea Wall to victory, kicking towards home to see off Tarsus and Charles Street.
In the next McCoy gave Williams his second winner with the 5-2 shot Danehill Willy.
A third victory followed in the penultimate race, the Office Visions Handicap Chase, as McCoy took another O'Neill horse, Nostringsattached, first past the post.
"It's a lovely track, and obviously the ground is probably a little bit quicker than they would have liked, but I'm sure they'll fix that," said McCoy.
"It's very similar to places like Newbury in lots of ways - there are no faults with the track."
It is hard to disagree with McCoy's assessment and it seems that Walters may have transformed a coal mine into a racing gold mine at Ffos Las.