UPDATE 2-Rugby-World-Pumas hang on for historic semi-final berth

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By Rex Gowar

PARIS, Oct 7 (Reuters) - Argentina hung on in the face of determined Scotland pressure to win their quarter-final 19-13 on Sunday and reach the last four in the World Cup for the first time.

In by far the least attractive match of the quarter-finals weekend, the tiring Pumas defended their tryline tooth and nail against a last-ditch Scottish onslaught to earn a semi-final against South Africa.

"We were very tired and Scotland played really well. We stuck with it, we wanted to be in our first semi-final and we are," Pumas captain Agustin Pichot told ITV television.

Argentine players and fans, some beating drums, became locked in a frenzy of soccer-style celebration as the Pumas, unlikely semi-final candidates when the tournament started a month ago, notched a historic fifth World Cup victory in a row.

The teams scored one try apiece, number eight Gonzalo Longo for Argentina in the first half and replacement scrumhalf Chris Cusiter for the Scots with 16 minutes remaining.

The difference between the sides in the end were six of the points from the boot of centre Felipe Contepomi, whose three penalties and a conversion took his tournament tally to 64 points.

The Argentines, notching their sixth successive victory over Scotland, had a nervous final quarter of an hour as Scotland, their dream of a second semi-final since 1991 ebbing away, threw everything they had into a potential match-winning try.