Priest's century was also the highest score by any White Fern against Sri Lanka and only the second ton since Debbie Hockley's unbeaten century in 1997.
It was quite the day for milestones, Sri Lankan bowler Inoka Ranaweera bouncing back from a caning off her early overs to take the first hat-trick by any international team against the White Ferns as she removed Anna Peterson, Erin Bermingham and Lea Tahuhu off the final three balls of the innings. Her 4-53 off eight overs was a career best.
A tally of 283/9 would prove a challenge for the visitors, however, on a day that oscillated between spring and summer as a southerly and light rain swept across Canterbury.
Attapattu (75) anchored the Sri Lankan innings in reply, but after the initial breakthrough was made courtesy of a Katie Perkins-effected run out, the Sri Lankan opener lost partners regularly and her team petered to 187/9 in their 50.
Twenty-three-year old White Fern Leigh Kasperek attacked for a career-best haul of 4-27 off her 10 overs, including two maidens.
The White Ferns pick up two valuable IWC points from the win. The second One-Day International is at the same venue on Thursday.
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