By Peter Rutherford
GWANGJU, South Korea (Reuters) - USA Swimming have filed an appeal following the disqualification of Lilly King from the women's 200 metres breaststroke heats on Thursday at the world championships in Gwangju.
King, the Olympic and world 100 champion, came home first in her heat but after looking up at the scoreboard she was stunned to see she had been disqualified.
When asked the reason she told reporters: "They didn't tell me."
USA Swimming said they were told it was for a "non-simultaneous touch" at the first turn.
Canada's Sydney Pickrem went through as the fastest qualifier in 2:24.53.
The disqualification is the latest controversy to hit the championships, which have been rocked by protests on the podium over controversial Chinese swimmer Sun Yang's participation at the meet.
Sun, who was sanctioned for doping in 2014, has been cleared to compete in Gwangju despite having another doping case pending at the Court of Arbitration for Sport.
After Sun's victory in the 400 freestyle on Sunday, silver medallist Mack Horton refused to share the podium with him, while British bronze medallist Duncan Scott would not shake his hand or pose for a group photo with Sun after Tuesday's 200.
The protests have prompted FINA into adding a clause to their code of conduct calling on swimmers to avoid "offensive or improper behaviour" during a competition.
Adam Peaty, who wrapped up a third straight 50/100 breaststroke double on Wednesday, has said the new rule will not stop him from speaking out.
"Athletes are always entitled to freedom of speech and when we detect that something is wrong and there's cheating, then why shouldn't we have a voice?" he told The Times.
"Any doping in the sport is a straight no from me."
'FASTEST FIELD EVER'
In the men's 200 breaststroke heats, Australia's Andrew Wilson swam 2:07.29, the fourth-quickest time of the year, to reach the semi-finals.
Britain's Ross Murdoch was fifth fastest, 1.76 seconds behind the Australian, and said the pace of the heats was incredible.
"It's the fastest field ever by a long way," said the Scot. "There's a few boys out there that are really touching on that world record."
Rio Olympics 100 freestyle champion Simone Manuel moved through to the semi-finals as the fastest qualifier, her 53.10 edging Swede Sarah Sjostrom by 0.01 seconds.
Cate Campbell, who swam a sensational anchor leg in the mixed 4x100 medley relay to overhaul Manuel and win gold for Australia, swam in the next lane to Sjostrom and qualified fourth fastest (53.36).
"Just needed to get through to the next round and that's exactly what I did. Didn't want to expend any more energy than you have to," she said.
"I knew having Sarah next to me, if she was pushing me then I'd get through to the semi-finals no worries. She's a good pacing buddy."
The evening session of the fifth day of the championships will feature the finals of the women's 200 butterfly, 50 backstroke and 4x200 freestyle relay, as well as the men's 100 freestyle and 200 individual medley.