Kevin Doyle and Liam Lawrence teamed up to send Paraguay packing as the Republic of Ireland claimed a World Cup scalp.
Doyle capitalised on a seventh-minute error by Manchester City striker Roque Santa Cruz to head the home side ahead at the RDS, and Lawrence added a second six minutes before the break in front of a delighted crowd of 16,722.
The South Americans, who beat Brazil and drew with Argentina in Buenos Aires during their qualifying campaign, flattered to deceive before the break, but were more of a threat after it and reduced the deficit through Lucas Barrios' fine 58th-minute strike.
However, despite a late flurry, they were unable to claw their way back as Giovanni Trapattoni's men claimed a creditable victory.
Ireland could have been forgiven for going into the game still smarting at not being able to join the Paraguayans in South Africa, but instead they chose to demonstrate that, regardless of Thierry Henry's illegal contribution to their downfall, they were good enough to be there.
Trapattoni readily acknowledges that he may not have as much natural talent at his disposal as some of his managerial counterparts, but he has learnt over the past two years that he has a team spirit, a pride and a passion which can make up for much of the shortfall.
That was in evidence once again at the RDS as a Paraguay side which in many ways was more technically gifted, failed to break down their hosts until the final seconds of the first half despite dominating possession for long periods.
Midfielder Cristian Riveros, who will be playing his football in the Barclays Premier League with Sunderland next season, was the architect of much of his side's better work, but all too often the South Americans were unable to make the most of his efforts and those of Enrique Vera alongside him.
But while the Republic's work may have been a little more prosaic, they were far more effective where it mattered and had scored twice by the time the first half drew to a close.
They were indebted to Santa Cruz for their opening goal, which arrived with just seven minutes gone.
Damien Duff and Lawrence worked a free-kick move before the Fulham man delivered the ball into the box, where defender Paul McShane attempted and failed to execute and hugely ambitious overhead effort.
But the ball reared up off the turf and Santa Cruz instinctively headed it on to his own crossbar, allowing Doyle to pounce on the rebound and score.
Paraguay might have hit back within two minutes, but midfielder Jonathan Santana's rising shot sailed over Keiren Westwood's crossbar, and Sunderland defender Paulo da Silva only just failed to connect with Rodolfo Gamarra's driven 32nd-minute free-kick at the far post.
However, Ireland extended their lead seven minutes later when Doyle chested down Stephen Kelly's cross to Lawrence, who thumped it past goalkeeper Aldo Bobadilla with the help of a deflection off defender Denis Caniza.
Westwood was called upon for the first time in injury time when he tipped Antolin Alcaraz's speculative effort around the post, but he was otherwise untroubled.
The Republic might have killed the game off within minutes of the restart after creating two good chances in quick succession.
First Doyle tested Bobadilla with a left foot shot on the turn from distance, and then the goalkeeper blocked Duff's shot with his chest after the winger had escaped Da Silva's clutches on the left.
However, Paraguay reduced the deficit with 58 minutes gone when Gamarra and Claudio Morel played their way around McShane for the former to slide a pass to Barrios, who dispatched it right-footed past Westwood.
Both managers made changes as Trapattoni handed senior international debuts to Cillian Sheridan, Paul Green and Keith Fahey, while opposite number Gerardo Martino dispensed with three-quarters of his starting midfield.
In the meantime, Westwood was grateful to see Gamarra's teasing 70th-minute cross run harmlessly out of play and Lawrence intercept substitute Aureliano Torres' superb pass to Gamarra with the visitors making a late push.
Man of the match Doyle made way for Shane Long to rapturous applause with three minutes remaining on another good night for Trapattoni and his players.
© Press Association