World number one Kento Momota was stunned by number 38 South Korea's Heo Kwang-hee on Wednesday, going down 15-21, 19-21 and looking visibly despondent at each lost point.

Badminton's comeback kid Momota has faced tremendous obstacles to get to the Tokyo Olympics — including serious injury in a car accident — and was expected to win the match.

Instead, he struggled to keep his head above water in the first game, overwhelmed several times by Heo's sharply angled smashes and unable to retaliate with his own.