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PARIS - Ireland will be looking to try and control Argentina first five-eighths Juan Martin Hernandez when the teams meet in their World Cup Pool D decider at the Parc des Princes on Sunday.
Coach Eddie O'Sullivan sees Hernandez as a major threat to Ireland's hopes of the big victory they need to make it to the quarter-finals.
"He's an excellent footballer... The move he's made to that position has made the Argentina team stronger," O'Sullivan said of Hernandez, who before the World Cup had almost always played at fullback for the Pumas.
Ireland, five points behind unbeaten Argentina, need to score four tries and win by more than seven points to avoid elimination.
The last time the Pumas conceded four tries was in a 68-36 victory over Japan in Buenos Aires two and a half years ago.
O'Sullivan said it would be a mistake to go into the match thinking of the four tries.
"Start thinking about racking up scorelines against the likes of Argentina and you're in trouble. Invariably, games against Argentina are quite tight," he told a news conference.
"At some point in the game, I don't know when, we may have to throw caution to the wind because this is not an orthodox situation," he said at Ireland's Paris hotel.
"First we have to win the game, that's paramount, and on the back of that get the tries we need."
Taking decisions whether to kick penalties, tap them or go for touch will "depend on the state of the game...(and) the odds of scoring the penalty."
O'Sullivan said prop Simon Best, who suffered a shock collapse in Bordeaux during the week, had been diagnosed with an irregular heartbeat but was now in good condition and would be able to go home on Tuesday.
"There's an element of relief (in the squad) that it wasn't more serious," he said.
Asked if such a setback could help galvanise the team, he said: "I think these things always do."
O'Sullivan said wing Andrew Trimble had been withdrawn from the bench and replaced by Gavin Duffy.
Trimble suffered an injury to a finger during the first pool match against Namibia, losing a nail, and it had become infected in the last 24 hours.
- REUTERS