A doping row involving Chinese athletes may prove to be a tinderbox at the Olympic swimming meet, where the United States faces the biggest challenge to their reign in decades.
Some of the worlds best in the sport have criticized anti-doping authorities and raised concerns about the competitions integrity following revelations in April that 23 Chinese swimmers were allowed to compete at the Tokyo Games despite testing positive for the banned heart medication trimetazidine (TMZ).
The World Anti-Doping Agency accepted the findings of a Chinese investigation that the test results were due to contamination from a hotel kitchen the team was staying at.
An independent investigation backed WADAs handling of the case in its findings this month, but for a number of Chinas rivals, questions remain.
American seven-time Olympic champion Caeleb Dressel put it bluntly when asked on Thursday if he felt confident of a level playing field.
