Teenager Jordan Petaia has starred on debut for the ill-disciplined Wallabies, who came alive in the second half to dispatch Uruguay 45-10 at the Rugby World Cup.

Winger Dane Haylett-Petty and outside centre Tevita Kuridrani both bagged doubles while winger Petaia crossed with his second touch as Australia ran in seven tries to one in humid conditions in Oita on Saturday.

The performance was marred by first-half yellow cards shown to forwards Adam Coleman and Lukhan Salakaia-Loto, both for high tackles, while Australia also suffered heavily in the penalty count.