South Australia batter Jake Fraser-McGurk smashed a 29-ball century against Tasmania at the Marsh Cup on Sunday to register the fastest hundred in one-day cricket, eclipsing South Africa great AB de Villiers' previous record of 31 balls.

Replaying to Tasmania's mammoth 435-9, South Australia were dismissed for 398 at the Karen Rolton Oval in Adelaide, but it turned out to be a memorable outing for Fraser-McGurk, who hammered 125 runs from 38 deliveries, which included 10 fours and 13 sixes.

The 21-year-old was eventually dismissed by off-spinner Beau Webster in the 12th over. Fraser-McGurk reached his half-century in 18 balls, the quickest by an Australian in the 50-over format.

"I went out there with some good intent, had my plans and process, and seemed like everything went my way," Fraser-McGurk said.

"I've made a few 30s playing in twos and stuff, felt like I've been hitting them reasonably well but probably not that well so definitely surprised myself."

The record also marked Fraser-McGurk's first century in any professional format.

"It's probably an innings I'll never see maybe ever again. It was some of the cleanest ball-striking I've seen and sometimes you've just got to tip your cap to players like that that can do that," Tasmania captain Jordan Silk said.

"Whilst it was frustrating to watch it was also amazing to watch."