Beaten by the same opposition 1-0 in a turgid affair 11 months earlier that ruined their dream of appearing at a first World Cup finals in 60 years, this was a new-look Wales as a vivacious new wave of young talent is being brought through by the Manchester United legend.
The likes of David Brooks, Connor Roberts, Chris Mepham and 17-year-old Ethan Ampadu all started the game and Giggs’ faith in his young Dragons was rewarded with a red-hot performance as a depleted Ireland were blown away.
Up next for Wales is a sterner test against Denmark, who reached the round of 16 at the World Cup. Here we look at three talking points ahead of the game:
ETHAN AMPS UP THE VOLUME
What a display. There were plenty of impressive performances all over the pitch for Wales on Thursday but the fact a 17-year-old novice fitted in so seamlessly on his first Wales start was beyond impressive.
A pass success rate of 88.2 per cent, one key pass, two aerials won, three tackles and two interceptions (both led Wales), seven long balls played (six found a team-mate) and a sumptuous assist for Aaron Ramsey to make it 3-0 – it’s safe to say that apart from his eye-catching dreadlocks, Ampadu stood out.
Perhaps we shouldn’t be surprised at the teenager taking to the big stage so well in his third appearance and first competitive outing.
This is a player who made his Exeter City debut aged just 15 and was impressive on his Chelsea bow under Antonio Conte against Nottingham Forest and later Bournemouth in the League Cup last season.
OK, so those arenas were low key compared to a competitive international fixture, so could he do it when it mattered? He answered emphatically.
What was even more impressive than seeing one so young stamping his authority on the game was the context in which it arrived.
This is a Welsh side in transition, still getting to grips with their new coach and trying to evolve and build on the excellent progress made under Chris Coleman.
Giggs was trialling a new shape, switching things up to a 4-3-3 and later a 4-2-3-1 from the 5-3-2 they have become accustomed to.
There will surely be teething problems ahead as Giggs tries new variations and players. But for now, can he leave Ampadu out of his starting XI on Sunday?
THE TIMES, THEY ARE A CHANGIN’
Not many football supporters and pundits will be found raving about Chris Gunter, but he is a talismanic figure among Welsh fans.
A solid, dependable player who never lets you down and someone who’s just always seemed to be there (he’s five games away from becoming his nation’s most capped player).
So to see him not in a Wales starting XI was odd. But the emergence of Swansea right-back Roberts is just one indicator of the sweeping change being initiated by Giggs.
Wales fans still high on the glory of reaching the Euro 2016 semi-finals were brought crashing down to earth when the wind beneath their wings was sucked away following dismal failure to make the 2018 World Cup.
Ashley Williams and Joe Ledley – key protagonists in France and stalwarts of the modern-day Wales – have seen their form fall off a cliff in the intervening two years.
Ledley, at only 31, looks a spent force and a commanding showing from captain Williams against Ireland cannot paper over the many cracks in his exposed armour.
As the famous Bob Dylan song goes, the times they are a changin’, and in Wales’ case, that means for the better.
Ampadu, Roberts and Mepham’s early steps into the international arena are encouraging in terms of looking at long-term replacements for Gunter, Williams and Ledley.
With Bournemouth’s summer recruit David Brooks also excelling on Thursday, Wales could be looking at a crop of players who can be their bedrock for the next decade.
NOW COMES THE REAL TEST
The Giggs reign is really under way and he has breathed new life into the Dragons, but his fledgling managerial skills will be put to the test against the Danes, who are set to be back at full strength.
Wales will face a very different Danish Dynamite side in Aarhus on Sunday than the one lacking any explosiveness in a 3-0 defeat to Slovakia in a friendly on Wednesday.
That Denmark had a student, a salesman and an internet star in their line-up after an extraordinary row between the Danish FA and their top players over a commercial rights dispute. A total of five players from the 24 called up were in Denmark’s national futsal squad for their last match against Greenland in May.
That resulted in top players like Tottenham’s Christian Eriksen and Leicester’s Kasper Schmeichel originally being unavailable for the national side.
Manager Age Hareide was told to stay at home for the Slovakia game as former Arsenal midfielder John Jensen took temporary charge, but he will be back, as will the big guns.
Sevilla’s Simon Kjaer, Chelsea’s Andreas Christensen, Ajax’s Lasse Schone, Borussia Dortmund’s Thomas Delaney and RB Leipzig’s Yussuf Poulsen are just a clutch of the names who will be in contention – and they will provide a far sterner challenge to Giggs’ new breed than an under-strength and woeful Republic.
It’s exactly the type of challenge Wales need and should relish.
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