Quinlan goes over for the try. (Getty Images)

By Gareth Duggan, PA Sport, Adelaide

Ireland's World Cup dream lives on after a night of intense rugby produced a memorable 16-15 win over Argentina in Adelaide to banish memories of heartbreak four years ago and conjure images of glory in the coming weeks.

After fighting off a ferocious Pumas onslaught the Irish took a 10-9 lead into the break then held their nerve in a manic final quarter to record the win which ensures at least second place in the group.

They now face Australia in Melbourne on November 1 knowing a win will enable them to avoid a probable quarter-final with France and thus open up the likelihood of a place in the semi-finals.

Ireland's heroes were many, with the wounded and disconsolate Alan Quinlan perhaps the most significant.

His try in the 20th minute came at a steep price as the effort of placing the ball over the line in a tackle cost him a dislocated shoulder and his continued participation in the World Cup. David Wallace is being rushed to Australia as a replacement.

Quinlan's try was set up by a bullocking run from captain Keith Wood and coach Eddie O'Sullivan saluted his skipper for another wonderful display.

"I thought it was the performance of a great captain," said O'Sullivan.

"Cometh the hour and cometh the man. He's been there before in tight situations and come out on the right side of them, so having someone like that out on the pitch certainly gives you an advantage," he said.

"He really showed great leadership."

Wood had to be at his best as Argentina threatened to completely overwhelm Ireland at times in the first half. The line-out misfired and required some hasty tuning at half-time, and their defence around the rucks was too flimsy.

As a result, Argentina should have scored at least one try before the break, but poor execution cost them their chances to capitalise on their general dominance of the first half.

Humphreys' conversion of the Quinlan try and a penalty seven minutes later pushed his side into a 10-3 lead but Gonzalo Quesada struck a drop-goal and a penalty to reduce the gap to just a point.

In the second half, Quesada missed a penalty but a Corleto drop-goal in the 57th minute put Argentina ahead again by a point, sending a shiver of nervousness through the massive contingent of Ireland supporters.

O'Gara responded with two penalties in three minutes before Quesada kicked a penalty with eight minutes left to set up a barnstorming finish.

The last act of the match saw full-back Girvan Dempsey dump Argentinian winger Diego Albanese over the touchline.

Afterwards, O'Sullivan admitted huge relief at the win.

"We knew going into it that a victory would put us into the quarter-finals and if we didn't we would have a mountain to climb going into Melbourne," he said.

"There was a lot of tension and a lot of pressure out there on both teams, so there's a great sense of relief now that we've won our three games and we're into the quarter-finals."

The physical, close-quarters nature of the match took its toll, with Quinlan the most serious casualty but plenty of other players suffering from inevitable minor wounds.

"There's a lot of bruised bodies out there, that game was as physical a game as we've been involved in at any time," said O'Sullivan.

Among them was Wood, who missed the post-match press conference because of nausea caused by dehydration.

"We are going to have to review everybody from a fitness point of view. We don't have a lot of injuries as such, but our guys got fairly well beaten up."

Argentinian skipper Agustin Pichot admitted his side had failed to settle themselves in the closing stages and lost their opportunity.

"In the crucial moments of the game we were not ahead and we lost composure in the last 15 minutes," said Pichot.

"In the last 15 minutes we missed a couple of line-outs and lost some possession, which was vital, and those mistakes cost us."

Full-back Ignacio Corleto, whose drop-goal had Irish hearts aflutter, summed up his team's feeling simply and eloquently: "It hurts."

For Ireland, the hurt is gone.