Dunno - LAX-SYD is 7,488 miles direct, without routing. Airbus says the max range with pax of a new A330-200 with increased range is 7,200 miles. (and that's the optimistic manufactuer, actual range is probably a bit lower).

Probably any A330s we would buy would replace other long routes like MSP-NRT or DTW-NRT while those 777 would go to others routes.