"It wasn't with the polish we wanted and I thought we left a lot of opportunities on the park, especially in the second half," Australia coach Dave Rennie said. "We went really hard first half. I thought that should have paved the way to run them off their feet but they are tenacious, they hang in there and scramble really well."
Kerevi's line-busting form alongside Len Ikitau was a highlight, as was Kellaway's form on the wing and Reece Hodge's effort at fullback.
Hodge deked and strongly skipped through two attempted tacklers for the game's first try, kicking and running strongly in general play as he made his case for the No 15 jersey after replacing Tom Banks, who broke his right arm last week against South Africa.
The 23,184-strong crowd, which had earlier watched the All Blacks beat South Africa 19-17 to clinch the tournament title, saw another strong performance from prop Taniela Tupou.
Skipper Julian Montoya scored for Argentina off the back of a maul to open the second half but a yellow card to Marcos Kremer for tripping Hodge hurt their hopes just before O'Connor came off the bench.
- AP
Here's how the match unfolded: