Steve Smith's fierce 50-over form continued in Sydney today with a match-winning century in NSW's 59-run win over Victoria in the Marsh One-Day Cup opener.

Smith, Australia's reigning men's ODI player of the year, posted 127 to make it three one-day hundreds for the summer after his pair of 612-ball centuries against India in November.

He was forced to play cautiously in the early stages as NSW slumped to 4-73 after 20 overs on a tacky wicket that offered enough sideways movement to keep the Victorian bowlers interested and the Blues batters honest.

But once the new ball lost its sheen and the sun poked its head out through the cloud cover, Smith displayed the attacking stroke play that was on show against the Indians to motor to his third one-day hundred in the sky blue of his state.

His first 50 came from 77 balls and his second from just 38 as he finished with a career-high six sixes in List A cricket. One six, a heave from outside off-stump off the bowling of James Pattinson, flew over the leg-side rope, the hill behind it and the venue's perimeter fencing.

Smith's knock was supported by a blazing debut 57 (41 balls) from youngster Oliver Davies and a career-best 49 (30) from captain Pat Cummins in his first match in charge of NSW.

Davies was impressive in his maiden knock, backing up his early KFC BBL form with the Sydney Thunder by launching three sixes, two onto the grassy bank in the same Xavier Crone over.

Having been sent into bat by Victoria captain Peter Handscomb, the Blues posted 9-318 from their 50 overs and the new skipper set the tone early in the run chase.

Cummins struck twice in the seventh over, including the wicket of Nic Maddinson for a duck, to leave the visitors reeling at 2-20.

Handscomb, who took a brilliant catch with body, and mullet, in full flight in the first innings, steadied the ship with Marcus Harris in a 59-run stand.

But when Harris was bowled by Sean Abbott for 47, the pursuit went off the tracks again, with Handscomb and Jake Fraser-McGurk falling soon thereafter.

Smith's day wasn't done, thrown the ball by Cummins to bowl for the first time this summer, his two overs costing 16 runs.

Meanwhile, Matt Short put together a rear-guard run-a-ball innings of 67 that kept the Victorians in with a sniff as wickets fell and the required run rate increased.

His dismissal, lbw to Liam Hatcher, left the hitting responsibilities to Pattinson, who clubbed a maiden one-day half-century and bombed three sixes in his entertaining 54 from 36 balls.

Cummins and Ben Dwarshuis collected the final two wickets to bowl the Vics out for 259 and win by 59 runs.