Fullback Kevin Morgan added a second-half try and the boots of Stephen Jones and Gavin Henson took care of the rest. Wales were forced to make late changes when backs Rhys Williams and Hal Luscombe failed fitness tests yesterday. Llanelli Scarlets veteran Mark Taylor came into the starting lineup in the unfamiliar No 14 jersey, with Ospreys centre Sonny Parker moving on to the bench.
O'Gara opened the scoring with a third-minute penalty goal as the Welsh lineout continued its rocky Six Nations, and things weren't looking good for the home crowd when Stephen Jones sprayed his first attempt at goal well to the left of the posts. The match was rocked by controversy in the 10th minute when Irish star Brian O'Driscoll stamped on the chest of Wales lock Brent Cockbain. The incident infuriated the crowd, but didn't upset the Welsh side, who responded immediately with a Henson dropped goal to level the scores.
And then came the moment that few Welsh fans at the stadium will ever forget. The ball came back to O'Gara, who kicked for touch - only it never got there. Loosehead prop Jenkins charged it down, toed the ball ahead and dived on it for one of the most popular tries Wales have ever scored. And as loud as the crowd were then, they found a few more decibels when Henson slotted a 52-metre penalty goal to give his side a 13-3 lead.
Stephen Jones pulled off a try-saving tackle on winger Girvan Dempsey, and Jenkins produced a monster hit on opposite number Reggie Corrigan as the home fans started believing in the Grand Slam dream. Jones and O'Gara traded penalty goals, and Wales took a crucial 16-6 lead into the break.
Jones extended that lead from point-blank range in the opening exchange of the second half, and O'Gara had the visiting fans looking for the exits when his attempt drifted wide. Jones twisted the knife with another goal, but Ireland refused to lie down. No 8 Anthony Foley was denied by the corner flag as he tried to narrow the margin, and the miss proved costly as Wales - spurred on by 74,000 voices - stormed back down the field.
A crucial lineout take from skipper Michael Owen - who had a brilliant game - gave centre Tom Shanklin the space to put Kevin Morgan over the line for a try that nearly brought the Millennium Stadium down. Jones's conversion took the score to 29-6 with 20 minutes to go, and the WRU were starting to clear out their trophy cabinet - not that it had a lot in it to clear out. Replacement prop Marcus Horan gave Ireland hope by charging over the try-line from close range, but that man Stephen Jones kicked his sixth goal of the afternoon to settle his fans' nerves.
Ireland fullback Geordan Murphy scored a late try from a cross-kick, but nothing was going to deny this Wales side the prizes they deserved after a famous Championship campaign.
Wales: 32 Tries - G Jenkins, K Morgan; Pens - G Henson, S Jones 4; DG - G Henson; Cons - S Jones 2
Ireland: 20 Tries - M Horan, G Murphy; Pens - R O'Gara 2; Cons - D Humphreys 2. Halftime: Wales 16-6
Referee: Chris White (England) Crowd: 74,000