Victoria 4 for 236 (White 86, Quiney 65, McDonald 2-47) beat South Australia 6 for 232 (Miller 47, Luderman 38, Christian 2-41) by six wickets
Victoria began their chase of 233 slowly, as Aaron Finch was run-out for 5 in the third over, but recovered with a 78-run stand for the second wicket between Quiney and Matthew Wade.
Wade hit three fours and two sixes, but departed for a 51-ball 44 in the 21st over, with Victoria needing another 147 off 29 overs. South Australia captain Johan Botha introduced Sam Miller into the mix to try and enforce their advantage, but Quiney and White stood firm and batted out the next 18 overs.
Quiney, who top-scored for Victoria in their last game against Tasmania, continued his good form, scoring a patient 65 that included just three fours. He found support in White, who scored an aggressive 89-ball 86 with six fours and four sixes.
Quiney was caught by Chadd Sayers off Kane Richardson in the 39th over but David Hussey, accelerated for Victoria, racing to an unbeaten 28 off just 23, and ended the match with a six.
South Australia were earlier propelled by a 64-run, sixth-wicket partnership between Tim Ludeman and Miller that took them to 6 for 232 in their 50 overs. Electing to bat, openers Michael Klinger and Phillip Hughes made a good start, scoring 69 off 15.4 overs, but Scott Boland - who struck twice in the 27th over - and Dan Christian picked up two wickets each to rattle their top and middle order.
South Australia were struggling at 5 for 148 before Ludeman and Miller's late surge took them to a competitive total.