Nigeria’s Segun Toriola, who advanced to the second round in the male singles on Saturday, was beaten 4-2 by his Japanese challenger, Niwa Koki, on Sunday.
Toriola, 41, beat Koki 9-11 in the first set before the Japanese rallied back to dominate the second set 11-5.
Koki also won the third set 11-7 before Toriola triumphed in the fourth set, leaving scores at 4-11.
At that point, it appeared the Nigerian would overpower his challenger for the rest of the match. But Koki was in no mood to concede.
The Japanese overpowered Toriola 11-6, 11-1 in the fifth and sixth sets respectively to bring total scores at 4-2.
Toriola was one of Nigeria’s medal prospects and his ouster is a big setback for Nigeria’s ambition to return home with medals.
Toriola, who is making a record appearance in the competition, had on Saturday beaten Dmitrij Prokopcov of the Czech Republic 4-2 in the Men’s Singles Round One.