Larkham, the world’s most-capped fly half, pulled out on the morning of the match with a knee injury sustained in training and Mortlock was unable to return for the second half after picking up a shoulder injury.

But Mortlock had already scored one of three first-half tries and kicked three goals to put his side into a commanding 25-3 interval lead and the Wallabies held off a spirited Welsh revival to secure a bonus-point victory which should see them top the group.

Australia were at one down reduced to 13 men after Drew Mitchell and Nathan Sharpe were sin-binned in separate incidents but they had plenty in hand to stave off at late onslaught by the plucky Welsh.

Full-back Chris Latham, second in Australia’s tryscoring list, touched down twice to take his overall total to 39 in 75 appearances and his World Cup tally to 10 in four matches.

In a tough and physical opening, Wales lost flanker Colin Charvis for a spell in the blood bin and centre Sonny Parker was carried off on a stretcher midway through the first half after hurting his knee in an innocuous tackle.

Kevin Morgan came on to replace him, with Thomas switching to the threequarters but the captain also went off on 21 minutes with a damaged shoulder, the result of a collision with Mortlock.

That meant the introduction of James Hook rather earlier than coach Gareth Jenkins had planned, the fly-half slotting in at inside centre, and the injuries appeared to have a destabilising effect on the Welsh.

Stephen Jones had cancelled out Mortlock’s second-minute penalty but he was wide with two further attempts while the game was technically still in the balance.

Australian rookie Berrick Barnes, a late replacement for Larkham, set up the first try on 15 minutes for centre Matt Giteau and the Welsh, under pressure for most of the first half, were undone by a 12-point scoring burst in a crucial six-minute spell before half-time.

George Gregan seized on a Welsh handling error to get Mortlock over and man of the match Latham finished off a sparkling handling move for his first try.

When number eight Jonathan Thomas forced his way over for Wales’ first try within four minutes of the re-start, the 71,022 crowd sensed a comeback but it was quickly snuffed out when Latham re-gathered his own kick to wrap up the match.

Winger Shane Williams grabbed a late consolation and Hook kicked a third goal to give some respectability to the scoreline but it could not mask a comprehensive win by the 1999 champions.