Taiga Semikawa's hopes for a final-round flourish at the Singapore Classic were dashed following a disastrous three-over-par 75.
Semikawa had been performing consistently all week at the Laguna National Golf Resort Club, but faltered when it mattered most as he dropped as many six shots, including a triple bogey on the par-three 17th hole.
The three birdies he made at the fifth, eighth and 14th holes did little to make up for that damage as he plummeted 21 places to end the week in a share of 60th.
The 22-year-old Semikawa finished on three-under-par 285 - a whopping 16 shots back of winner Ockie Strydom.
"It's a pity that I could not achieve my goal to finish under par today," lamented Semikawa, who's formerly the world's number one amateur player.
"It took just one bad hole to ruin the day for me, otherwise it could have been a decent day.
"I didn't do too badly and in fact, my confidence was growing gradually.
"All I need to do is to play with more confidence and have more faith in myself."
Semikawa will now switch his attention to the Thailand Classic, the next DP World Tour stop, which he also gets in through a sponsor's invitation.
Australia's Anthony Quayle, who's the other JGTO member seeing action in the weekend, closed with a 70 to tie for 34th on nine-under-par 279.
Ockie fired a sparkling 63 to win by one shot from Finland's Sami Valimaki, marking his second win of the season after having captured the Alfred Dunhill Championship in December.