China's defending Olympic champion Chen Ruolin led the women's 10m platform preliminaries at London Games on Wednesday, determined to take the gold medal for China after her teammates lost the men's springboard title to Russia on Tuesday.

Chen, winner of the event at Beijing Games, scored 392.35 points in the heats, a bumper 43.35 points over second-placed Pandelela Rinong Pamg from Malaysia who ended the night with 349 points.

Though leading the field with significant margins, Chen said she was not very satisfied with her performance in the preliminaries, in particular, her second and fourth dives.

German diver Christin Steuer, who only entered the competition at the last minute following the withdrawal of her teammate Nora Subschinski with injury, dived consistently well to qualify third best with 341.75 points.

Another Chinese diver Hu Yadan, silver medalist behind Chen at the 2011 Shanghai World Championships, cruised into the semifinal with a sixth place of 18 qualifiers.

In a night where many failed to execute their five dives consistently, Mexican star Paola Espinosa Sanchez, silver medalist in the synchronized event earlier in the Games, produced a disappointing second dive - back three-and-a-half somersaults in tuck position - to score just 39.60 points which saw her slip to 18th after three rounds.

She managed to claw her way back up the with a solid fourth and fifth dives and finished 13th overall.

There was no better news for the home crowd as British Monique Gladding finished 19th, one place below the cut.

Gladding qualified for the London Olympics just months after plummeting to the water unconsciously after hitting her head on the platform in Russia.

South Korean diver Kim Suji, youngest diver of the London competitions at an age of 14, failed to progress to the semifinal finishing in last place.

Chen, who retained her title in the synchronized platform event earlier in London, was determined to grab the sixth gold medal for the diving powerhouse on Thursday.

The top 18 finishers in the 26-woman field advanced to Thursday morning's semifinals, and the top 12 finishers at the semis will qualify for the final scheduled on Thursday evening.