Ireland's Leona Maguire finished in a tie for 20th place on three over par after firing a final-round 75 at the Australian Ladies Classic in Bonville.
Playing in her first Ladies European Tour event since turning professional last summer, Maguire ended 11 shots behind winner Swede Marianne Skarpnord.
Maguire had recorded rounds of 73, 75 and 68 to move to level par but fell back on Sunday with a no-birdie round.
The County Cavan woman carded bogeys at the first, third and 13th holes.
Skarpnord enjoyed a two-shot lead over Nuria Iturrios of Spain and Australia's Hannah Green at the conclusion of the tournament.
Maguire, who was the top-ranked amateur in women's golf for 131 consecutive weeks, earned a Tour card in December.
She played in numerous events on the Ladies PGA Tour and European Tour during a glittering amateur career and won the Ladies British Amateur Championship in 2017.
She finished fifth at qualifying school to secure the highest category card available for the 2019 season.