Wales advanced to the semi-final of the Rugby World Cup with a gripping 22-10 victory over Ireland on Saturday thanks to a steely defence and superiority at the breakdown. It was the first time the Welsh, for whom captain Sam Warburton excelled in the loose and centre Jamie Roberts stood out as a midfield battering ram, had made the last four since the inaugural World Cup in 1987. The result continues Ireland's history of having never advanced beyond the quarter-final stage, which they have reached on no fewer than four occasions. Wales scored three tries through Shane Williams, Mike Phillips and Jonathan Davies, Rhys Priestland hitting two conversions and Leigh Halfpenny bagging a long-range penalty. Keith Earls scored Ireland's sole try, Ronan O'Gara claiming a penalty and conversion as Wales dominated the breakdown and nullified the Irish attack with an aggressive rush defence. "It was a massive performance, a massive defensive effort from 1-15," said Warburton, whose side stunned Ireland with a Williams try in the opening minutes. "We always say we don't start games well enough but our start was perfect," Warburton added. Dejected Ireland skipper Brian O'Driscoll, whose team beat Australia 15-6 in the pool phase, couldn't hide his dejection after what could be the centre's last shot at World Cup glory. "We got outplayed in the second half, they scored two good tries, maybe a bit of weak defence, but I'm very disappointed to be going home. "It was a great opportunity for us, winning the group. But they showed they are worthy semi-finalists, good luck to them. "When you turn the ball over that many times against good opposition, they make you pay," the 32-year-old added. Wales, knocked out of the last World Cup in France four years ago at the group stage, got off to a flying start when veteran wing Williams showed all his predatory skill to score his 56th try in his 84th match for his country. Charges from Roberts and Dan Lydiate set the Welsh up, a quick ball down the right wing enabling Halfpenny to suck Earls out of position and Williams to nip in at the corner, Priestland nailing the conversion. With the wind swirling around the stadium, O'Gara spurned two chances to go for goal as Ireland pressed for a response. Williams, at 34 the veteran of the young Welsh backline, then managed to produce a great try-saving tackle on Sean O'Brien as the flanker crossed the line, and another on Connor Murray from the ensuing scrum. When Rob Kearney was hauled down just short of the line, the ball was turned over but an infringement at the ruck handed O'Gara a kickable penalty. Halfpenny hit straight back with a 49-metre penalty as Warburton and Toby Faletau won the battle of the vaunted back-rows and O'Gara struggled to find his range out of hand. Earls handed Ireland the best possible start to the second period, the wing sliding in for a try despite Phillips's covering tackle. O'Gara hit the tricky touchline conversion to draw the scores level at 10-10. But Phillips restored Wales's lead with a clever dart down the blindside from a ruck 15 metres out. The scrum-half fended off Gordon D'Arcy and launched himself spectacularly for the line, dotting down one handed as Tommy Bowe came in with the tackle. Priestland's conversion drifted wide and the fly-half, whose form has seen him keep Stephen Jones and James Hook out of the team, then saw a 58th minute penalty come back off the upright. Ireland were then caught napping out wide and a quick ball from Phillips found Priestland, who offloaded to Davies, the centre splitting Cian Healy and Earls and riding Eoin Reddan's weak tackle for a fine individual try. Priestland hit the conversion to make it 22-10 with 15 minutes to play, the Welsh showing excellent fitness and resolve in the loose to keep the Irish at bay. They now face the winners of Saturday's other quarter-final, between England and France, in the last four in Auckland on October 15.