(BSS/AFP) - Chinese 12-year-old swimming sensation Yu Zidi could be the brightest young star at this year`s world championships after producing a string of eye-popping performances this week.

Yu, in her striking "doggy" swim cap, rounded off a sensational China national swimming championships in Shenzhen by winning the women`s 400m individual medley by almost two seconds on Saturday.

Roared on by packed crowds in the southern city which borders Hong Kong, Yu crushed a quality field in a lifetime best 4min 35.53sec.

Yu`s time was comfortably inside the world qualifying standard of 4:43.06, the fifth fastest time of the year and would have been good enough for fourth place at the Paris Olympics.

Second was Chang Mohan, who touched more than a body length adrift in 4:37.33, followed by Li Bingjie in 4:38.66.

It came just a few days after the 12-year-old`s 200m butterfly gold in a scarcely believable 2:06.83, also fifth fastest in the world this year and another time that would have garnered a fourth place in Paris.

"My lungs were about to explode!" Yu said after that win, according to state news agency Xinhua. "I didn`t know my time. I just focused on my pace, stroke-by-stroke."

Yu started the week-long China championships by taking second in the 200m individual medley behind Paris Olympian Yu Yiting, with another world-qualifying time of 2:10.63.

That prompted the global governing body, World Aquatics, to post: "12-year-old sensation alert!" on X.

The China meet serves as trials for the world championships, which take place in Singapore from July 27 to August 3, with the top two in each event eligible for selection, providing they have met the qualifying standard.

Yu said it would be "cool... to compete internationally in a swimsuit adorned with the national flag and my doggy cap", reported Xinhua, giving a nod to her black-and-white swim cap emblazoned with a cartoon puppy.

China`s swimming association told AFP it would finalise its team for the worlds after the national championships concluded on Saturday, without confirming if Yu would be included or giving a date for a squad announcement.

Yu, who turns 13 in October, trains in the northern province of Hebei and has been earmarked as a "prodigy" by Chinese state media since first making national headlines last year.

Fellow Hebei native 23-year-old Li, whom Yu has called an "idol", may have been only third behind the 12-year-old on Saturday, but she dominated the women`s freestyle in Shenzhen with golds in the 200m, 400m, 800m and 1500m.

Men`s 100m freestyle world record holder Pan Zhanle, 20, won four individual golds and teamed up with the returning three-time Olympic gold medallist Sun Yang, Wang Shun and Fei Liwei to win the men`s 4x200m freestyle relay.

But the disgraced 33-year-old Sun, the first Chinese man to win an Olympic swimming gold, will not be going to the world championships.

He recently returned to action after serving a four-year ban for a doping violation and China forbids those who have been suspended for 12 months or longer for doping from representing the country.