Marcos Ayerza's hopes of playing in the Rugby World Cup Final were ended on Sunday evening when Argentina lost 29-15 to Australia in their semi-final at Twickenham.Adam Ashley-Cooper scored a hat-trick of tries for the Wallabies, who led from the second minute when lock Rob Simmons intercepted Nicolas Sanchez’s pass to score under the posts.   Argentina conceded two further first-half tries to Ashley-Cooper, but kept themselves in the hunt thanks to five Sanchez penalties.   Argentina trailed 22-15 going into the final quarter, but their hopes of victory were ended by Ashley-Cooper’s hat-trick score eight minutes from time, the winger given a simple try after a stunning run off the opposite flank by Drew Mitchell.   Australia will face the defending world champions New Zealand in the Final at Twickenham on Saturday. Argentina will contest the Bronze Final with South Africa at the Olympic Stadium on Friday evening.