China's Xu Xin won the men's singles title for the fourth time at the International Table Tennis Federation Korean Open after beating compatriot and reigning Olympic champion Ma Long in the final.
Xu, the second seed who won team Olympic gold at Rio 2016 and boasts 10 World Championship titles, came through 7-11, 11-6, 11-9, 11-7, 11-8 at the Sajik Arena in Busan.
It re-confirmed the 29-year-old as the dominant force at the event as no other player has won it more than once.
Xu also triumphed in 2013, 2014 and 2016 when the tournament was held in Incheon.
In 2013 and 2016 he also beat Ma, the fourth seed who won both the singles and team titles at Rio 2016, in the final.
His success means he has won twice in a row on the ITTF World Tour after also winning the men's singles at last month's Japan Open in Sapporo.
That was part of a historic hat-trick of victories which also included the men's doubles and mixed doubles titles.
He became only the second player to achieve this "triple crown" and narrowly missed out on achieving the same feat again in South Korea.
Xu won the men's doubles title with Fan Zhendong yesterday but missed out in the mixed final, losing alongside Liu Shiwen to Hong Kong's Wong Chun Ting and Doo Hoi.
Both finalists had to come through last four clashes earlier in the day with Xu beating compatriot and qualifier Wang Chuqin 8-11, 20-18, 11-7, 11-7, 5-11, 11-5.
Ma ended home interest in his last four encounter by beating South Korea's number 13 seed Jeoung Youngsik, the 2015 winner, 11-7, 5-11, 11-7, 11-6, 11-9.
In the women's tournament gold again went to China as second seed Chen Meng saw off top-seeded team-mate Ding Ning in the final.
Chen, a triple World Championship winner, came through 11-5, 11-6, 11-5, 7-11, 11-9 to secure the title.
She had earlier beaten seventh seed Wang Manyu, who she won the women's doubles crown with yesterday, 11-3, 8-11, 11-3, 12-14, 10-12, 11-9, 11-6 in the last four.
Ding, the singles and team Olympic champion from Rio, defeated another Chinese player in Sun Yingsha, the 16th seed, 8-11, 11-5, 8-11, 9-11, 11-8, 11-6, 11-8 in her semi-final.
Chen's win was her third on the World Tour this year following successes in Hungary and China.
It was her maiden Korean Open title after she lost last year's final to compatriot Zhu Yuling.
The next event on the World Tour calendar is the Australian Open in Geelong, which is rated as a top-tier platinum event.
Competition will take place between July 11 and 14.