Leona Maguire finished in a tie for 31st at the LPGA Thailand, 13 shots behind the winner, home favourite Paphangkorn Tavatanakit.
A pair of birdies on the back nine undid the damage of the same number of bogeys before the turn, but the Cavan golfer couldn’t make any further ground up the leaderboard thereafter. Her final round 72, level par, left her on eight-under overall, the same mark as nine other players.
Tavatanakit carded a final round 67 to leave her top of the pile by a single stroke by the end of Sunday’s action.
Meanwhile, PGA Tour rookie Jake Knapp carded 11 birdies during an eight-under 63 on Saturday to open up a four-shot lead after three rounds of the Mexico Open at Vidanta in Vallarta.
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Padraig Harrington, who started the day seven shots off the lead, carded a one-over 72 as he slipped back into a tie for 57th on three under.
Knapp's 19-under 194 matches the 54-hole record at Vidanta set last year by Tony Finau, who won the event.
Fellow rookie Sami Valimaki of Finland is second after a four-under 67.
Knapp had seven birdies on the front nine while shooting a stellar 28. He had four birdies and three bogeys on the back nine of his ninth career PGA Tour start. The 29-year-old Knapp will be looking for his first PGA win on Sunday.
Knapp would be the third player this season to win for the first time, joining Frenchman Matthieu Pavon (Farmers Insurance Open) and Nick Dunlap (American Express, as an amateur), both in January.
Valimaki had six birdies - including three in succession on the front nine - and two bogeys in his 11th PGA start. It was his second straight 67 after an opening-round 64.
Canada's Ben Silverman (63), Sweden's Henrik Norlander (65) and Chan Kim (66) are tied for third at 201, seven shots off the pace.
Knapp and Valimaki were part of a four-way tie for the second-round lead. The other co-leaders were Englishman Matt Wallace (71 on Saturday) and Mexico's Alvaro Ortiz (73). Wallace is in a tie for sixth at 202, while Ortiz is tied for 13th at 9-under.