Steve Smith remains "chilled" over the Australia captaincy after acting as deputy to Josh Hazlewood when the bowler stepped in for Pat Cummins in the ODI victory over England.

Skippers Cummins and Jos Buttler were afforded time to rest on Saturday in the second ODI, which Australia won by 72 runs to seal a series victory shortly after competing at the T20 World Cup.

Smith crafted a fluent 94 in Sydney to add to his unbeaten 80 in Thursday's Adelaide Oval clash, while being named as vice-captain to Hazlewood.

In-form batter Smith has only captained his side once – in The Ashes at Adelaide in 2021 after Cummins was ruled out due to COVID-19 – since the 2018 ball-tampering scandal against South Africa.

The 33-year-old insisted he remains relaxed over the captaincy decisions, though, with his focus on helping Australia regardless of his job description.

"I'm not sure if there was a conversation - I just do what I'm told," Smith said.

"I was vice-captain for this game, and helped out where I could. They're looking to build some new leaders, some younger leaders.

"I'm pretty chilled, I'll just do my thing."

Smith declared his innings against England in the ODI opener as the best he has felt batting in six years and reiterated his confidence after another impressive showing in the middle.

"It's my movement, my hands, the time I feel like I've got and just where I'm hitting the ball. I feel like I'm in a good place," he added.

Adam Zampa and Mitchell Starc did the damage with the ball against England, combining for eight wickets, and the leg-spinner acknowledged the importance of defeating dual world champions England.

"It's a series win, that's important to us against a good England side," Zampa told BT Sport.

"[James] Vince and [Sam] Billings made it look like it was going to be tough but we got a couple of big wickets.

"It was a hard wicket to start on. It was going to swing early, we felt the wicket was up and down. We knew reverse swing would come in later, and we made it tough for them.

"We're disappointed with how the World Cup went, England deserved to win but it's nice to get this series."