Szocs produced a superb display to stun the South Korean player, the world number eight, with a battling 11-5, 11-7, 7-11, 3-11, 11-7, 11-8 triumph at the Namdong Gymnasium in Incheon.

The Romanian, ranked at number 89 in the world, had to progress through the qualification rounds to reach the main draw of the competition, part of the ITTF World Tour.

"I feel unbelievable beating a top 10 world ranked player - it is even more spectacular to do it in Korea against the top seed in the tournament," said Szocs.

"At this stage with the number one seeded player eliminated anything is possible, I am optimistic and will try to do my best. 

"My objective for this tournament was winning in the first round so I can enter the top 64 seeding list for the World Championships. 

"I don't want to settle with this result but wait until the end of the competition to be able to enjoy it."

There were no such difficulties for Germany's Timo Boll, seeded third, as he swept aside Park Jeong-woo of South Korea 11-5, 11-5, 11-9, 11-8.

Fourth seed Koki Niwa of Japan also accounted for a player from the host nation, beating Cho Seung-min 11-5, 11-6, 11-8, 5-11, 12-10.

In the women's singles, three-time Olympic medallist and top seed Feng Tianwei of Singapore cruised into the second round with a comfortable 11-5, 11-5, 14-12, 11-7 win against Saki Shibata of Japan.

However, there were a number of surprise results as Yu Mengyu of Singapore's return to action for the first time since last year's Olympic Games in Rio de Janeiro ended prematurely with a 12-10, 8-11, 11-4, 12-10, 12-10 reverse at the hands of Japan's Minami Ando.

Mima Ito of Japan, seeded fourth, also lost as she was beaten 11-3, 11-8, 6-11, 2-11, 12-10 by South Korea's Lee Zion.

The tournament in Incheon continues tomorrow.