RIO DE JANEIRO • Britain's Jack Laugher and Chris Mears dethroned reigning champions China to claim their country's first-ever diving gold medal in the men's 3m springboard event.

Chinese divers had been targeting a sweep of all eight gold medals in the Rio diving competition, after winning six in 2012.

But on Wednesday, China's Qin Kai and Cao Yuan had to settle for third, with a score of 443.70 compared to Britain's 454.32.

The Chinese team, led by Qin, had held the title since the Beijing Games in 2008.

Sam Dorman and Mike Hixon of the United States took silver (450.21) after recording 98.04 - the highest score of the competition - for their final dive.

"We're so overwhelmed with what we've done," Laugher said. "The dream's happened."

Qin, who was widely expected to take home his third Olympic gold, said he was disappointed with his performance.

"I feel like I've let (China) down... of course we don't want this result," he said. "But, since it's like this, we can still gracefully lose, because our rival teams are also all very strong."

The problem of the water in the diving pool turning green worsened on Wednesday as whatever was ailing the pool migrated (albeit in a lighter shade of green) to the nearby pool used for water polo and synchronised swimming.

But Olympic officials said that, after extensive tests, they had finally pinpointed the reason: a chemical imbalance caused by too many people using the water.

"Mid-afternoon, there was a sudden decrease in the alkalinity in the diving pool, and that's the main reason the colour changed," Mario Andrada, a Rio 2016 spokesman, said.

Fina, however, issued a statement saying that "the reason for the unusual water colour... is that the water tanks ran out some of the chemicals used in the water treatment process. As a result the pH level of the water was outside the usual range, causing the discolouration". It insisted that there was no health risk to the athletes.

REUTERS, NEW YORK TIMES