Lauren Jackson saved the best game of her Opals comeback for last, starring for Australia as it clinched World Cup bronze with a 95-65 defeat of Canada in Sydney.

Meanwhile, USA defeated China 83-61 in the final in front of a sell-out crowd of nearly 16,000 spectators to win its 11th World Cup and fourth in a row.

Jackson confirmed just hours before tip-off her Opals comeback would conclude after the World Cup, where she played all eight games for Australia following an absence of nine years from the national team.

Following a second-half rampage that helped her finish with 30 points — the second-highest tally for any player in a single game this World Cup — Jackson left Australian fans to wonder whether she might reconsider her retirement.

"This journey has been the most humbling and most incredible 10 months of my life," Jackson said.

"It's given me an opportunity to play the sport I love in front of Australians again.

Opals coach Sandy Brondello had alluded to the fact Australia's bench would play a big role in the bronze-medal game, which took place just 16 hours after their semifinal loss to China.

But even Brondello had not predicted just how pivotal her 41-year-old former teammate would be.

"Who scores 30 points in a game?" Brondello asked reporters after the game.

"Lauren changed the game with her presence inside."

Jackson's first points, a jump shot, sparked an 8-0 Australian run that helped the home side quash Canada's early dominance.

Across the board, the Opals shook off the shooting woes that thwarted them in the tight semifinal defeat.

Australia's best player across the World Cup, Steph Talbot, was the chief architect as the home side maintained their lead over Canada in the second quarter.

Talbot had 11 points for the period — including a clutch three-pointer in the final seconds — to go with some trademark defensive efforts as the Australians took an eight-point lead into the main change.

She was later named in the World Cup's All-Star Five for her starring role in the Opals' campaign.

Canada's Kia Nurse contributed almost half of Canada's first-half points (19 of 43) with a versatile shooting display that made it easy to forget the World Cup had marked her return from an 11-month ACL injury lay-off.

With Canada still very much in the game after half-time, Nurse left the court after two fouls in quick succession and Australia needed to capitalise on her absence.

The majority of Australia's best players were coming off big minutes in Friday night's semifinal so the Opals found a hero in their greatest player of all time, who only made a cameo against China.

Jackson's points this tournament have come almost exclusively from beyond the arc.

But in the third quarter, she came alive in the paint and finished the third quarter with 13 points as Australia stretched out to what was ultimately a game-winning lead.

Her seven rebounds and two steals were personal bests for the tournament and when she kept her hot form up in the final quarter, the Opals were home.

Jackson left the court to a standing ovation in the final three minutes as the greatest basketball career Australia has ever seen officially came to an end.

"Right before the game it just dawned on me, it literally just hit me that this was going to be the last game that I'd play for Australia," Jackson said.

"I think because of how special this whole tournament has been and this journey has been for me, I got pretty emotional about it."

USA dominates China

A'ja Wilson scored 19 points and Kelsey Plum added 17 to help the US to another World Cup title.

The result was the biggest win in a gold-medal game, surpassing the 20-point victories that the US had recorded twice in previous editions of the tournament.

The US did it on both ends of the court, playing stellar defence as well as using a high-powered offence.

They finished the World Cup averaging 98.8 points, just short of the mark held by their 1994 squad that averaged 99.1.

The average winning margin was 40.8 points, topping the mark held by the 2010 US squad.

China trailed 33-28 late in the second quarter before the US went on a 10-2 run highlighted by fast-break lay-ups by Breanna Stewart and Wilson to extend the advantage to double-digits.

Jin Weina hit a three-pointer just before the half-time buzzer to get China back to within 10.

The US was just too good to let the upset happen, outscoring China 25-14 in the third quarter before icing the victory in the final term.

China won its first medal since the 1994 World Cup held in Sydney when the team also took the silver.

The victory was the 30th in a row in World Cup play for the Americans, who have not lost since the 2006 semifinals against Russia.

The crowd was the largest to attend a women's World Cup game since the the inaugural tournament in 1953 in Chile.

AAP/AP