Pan even failed to reach the final in 100m in Singapore, finishing 10th in the semis with a mediocre 47.81 on Wednesday, exactly one year after he stunned the world at Paris 2024 by clocking a new world record of 46.40 to win Olympic gold in the sprint event.

Pan also failed to reach the 200m semifinals at his fourth worlds, showing that he remains a long way from recovery, both mentally and physically, from the heavy toll taken by his Olympic preparations.

"Tenth place!?" Pan responded in disbelief when told the 100m result, before admitting: "I am not in good shape."

Following his breakout performance in Paris, Pan became a celebrity beyond the country's sporting circles, drawing a surge of media and public interest that disrupted his training. When he returned to the pool at the end of 2024, Pan admitted he was far from competitive.

"His form at the Olympics was 100 out of 100. Now, maybe 20 out of 100," coach Zheng Kunliang said in a TV interview in November.

Similar performance slumps also saw Tokyo 2020 women's 200m butterfly gold medalist Zhang Yufei, men's 200m medley Olympic champion Wang Shun and former backstroke world champion Xu Jiayu head home empty-handed.

"This is the first international competition of the new Olympic cycle," China's head coach Cui Dengrong told Xinhua. "Our focus is on developing young athletes and coaches, while assessing our standing on the world stage."