James McClean was the hero as his ferocious strike sent Republic of Ireland into the World Cup qualification play-offs at the expense of Wales.
Passionate Wales come out on the offensive
The equation was far from simple. A win for Wales would guarantee them at least a play-off place but they also held a chance of automatic qualification if Serbia slipped up against Georgia. An Ireland win would secure them second place and send Wales packing, whilst a draw would give Wales a chance of reaching the play-offs if results in other groups went their way to ensure they weren't the ninth best runners-up. In short, both teams were setting their stalls out to win.
If the domestic familiarity of the two line-ups mixed with the importance of the tie whilst combining the tension still residing from that tackle on Seamus Coleman by Neil Taylor did not ensure the contest was already at boiling point, then the passionate Welsh national anthem sung without music did little to cool the temperature.
Unsurprisingly, both sides flew out of the blocks but it was the hosts who used the overwhelming support to their advantage in the opening minutes. Ireland failed to clear their lines before Joe Ledley picked out Hal Robson-Kanu who glanced a header just wide.
The home side continued to push forward and Aaron Ramsey forced Darren Randolph into an excellent save as the goalkeeper tipped over a 25-yard thunderbolt. The Welsh were clearly dominating proceedings, boasting 85% of possession in the opening 15 minutes, but Ireland began to settle into the tie with their more conservative approach.
Ireland weather the storm
The visitors looked at their most dangerous from set-plays with Jeff Hendrick constantly finding himself in the right place at the right time. However, he could not get his radar right, as he did against Everton last weekend, firing a poorly cleared corner over before miscuing a long throw from Cyrus Christie in the penalty area.
Wales were beginning to lose some of their tempo and became restricted to long shots. Tom Lawrence could not repeat his heroics against Georgia as he fired a strike straight into the arms of Randolph.
If anything, Ireland were beginning to look the most threatening. Another free-kick was barely dealt with by Wales and Ciaran Clark played the ball into the path of his central defensive partner Shane Duffy, only for the Irish cult hero to fire wide from just inside the box.
Despite losing Joe Allen to injury on 37 minutes after being crunched between two opponents, the hosts produced an opportunity of their own from a set-piece as Ledley picked out Ben Davies but the left-back could only slice over with his weaker right foot.
Wayne Hennessey was finally forced into a save just before the break as Robbie Brady fired a shot straight at the Welsh goalkeeper. However, the sides trudged back to the dressing rooms with the scoreline goalless and everything still to play for.
McClean executes a ferocious strike to send Irish fans into pandemonium
After a tense and tight opening to the second half, Wales began to turn the screw and went close to breaking the deadlock on a number of occasions within the space of two minutes. James Chester headed into the side-netting from a corner before Robson-Kanu saw another header expertly tipped over by Randolph after a brilliant cross from substitute Jonny Williams. Davies then nodded over from the resulting corner as the home crowd began to find their voice again.
However, the hosts were soon made to pay for not taking their opportunities. Ashley Williams has lacked confidence in the Premier League this season and he was caught in possession by Hendrick. The midfielder powered down the touchline and pulled the ball back to James McClean before the left winger connected beautifully after a Harry Arter dummy to fire Ireland into the lead and a potential play-off spot. It was the first time Wales had fallen behind throughout the entire qualification campaign.
Elsewhere, Croatia took the lead against Ukraine to leave Wales needing two goals as a draw would result in Wales being the ninth best runners-up and missing out on the play-offs.
Irish hold form to burst Welsh bubble
Wales responded by throwing on Ben Woodburn and Sam Vokes in between Robson-Kanu flicking a header over and Aaron Ramsey striking wildly off-target from range. Meanwhile, Croatia doubled their advantage.
With Gareth Bale missing through injury, Ramsey was the man Welsh fans were pinning their hopes on to inspire the home side back into the contest. Yet the Welsh rhythm was flat, reflected by the atmosphere, as their only attempt for a large period was a wayward Ramsey free-kick.
Ramsey saw a late strike drift into the arms of Randolph as Wales failed to issue a response and Ireland celebrated getting their name into the hat for next Tuesday's play-off draw.