Thai shuttler Ratchanok Intanon can hardly be blamed for thinking the match was done with, when she walked to the net as if to congratulate her OUE Singapore Open opponent yesterday.
But she actually had one more point to play against China's Han Li.
While her concession was premature, a quarter-final defeat had long looked certain for the reigning world champion at the Singapore Indoor Stadium.
The world No. 4 was eventually beaten 21-14, 21-12.
Han, the world No. 17, will face defending champion Wang Yihan today.The world No. 3 Chinese swept aside P.V. Sindhu of India 21-19, 21-15.
Said Ratchanok who appeared sluggish throughout and was often late in her returns: "My opponent came prepared to give me a good fight today. She kept attacking my weak spots and I just couldn't hold out."
A calf injury from the All England Championships last month had derailed her training and preparations, added the 19-year-old, who is competing in her first tournament since then.
Having spent a week at a recovery centre before flying to Singapore, Ratchanok had also barely strung two days of training together in her lead-up to the tournament. Said her coach Xie Zhihua: "She's still not back at a 100 per cent so we came here without any targets. We're actually quite pleased that she managed to make it this far."
Han's victory meant that three of the women's singles semi-finalists hail from China, after world No. 1 Li Xuerui beat Chinese Taipei's Tai Tzu-ying 21-10, 21-13.
In the men's singles, Malaysia's Lee Chong Wei continued his dominance with another straightforward victory, this time beating Thailand's Tanongsak Saensomboonsuk 21-8, 21-14.
The world No. 1 was rarely troubled by his world No. 23 opponent, whose only flair was limited to a shirt collar turned up a la Manchester United great Eric Cantona. This was Lee's ninth straight victory over the Thai.
He will play India's K. Srikanth in the semi-finals today.
Indonesia's Simon Santoso will take on China's fifth seed Du Pengyu in the other semi-final.
When asked if he feels he has yet to be challenged so far in the tournament, Lee said: "I think many players, myself included, find it hard to play in this venue.
"But I probably adapt better than others."
In the men's doubles, South Korea's Kim Sa Rang and Yoo Yeon Seong sent world No. 1 Mohammad Ahsan and Hendra Setiawan packing, beating the Indonesian pair 21-15, 13-21, 21-19.
They will meet China's Cai Yun and Lu Kai today.
The other semi-final will feature another South Korean pair.
Ko Sung Hyun and Shin Baek Choel were handed a walkover by Chai Biao and Hong Wei of China after Hong came down with acute skin rashes. They will play Chinese Taipei's Lee Sheng-mu and Tsai Chia-hsin.