Tennis-Australian Open organisers deny slack COVID testing

Tennis - Australian Open - Melbourne Park, Melbourne, Australia - January 19, 2022 Germany's Alexander Zverev in action during his second round match against Australia's John Millman REUTERS/Loren Elliott

MELBOURNE (Reuters) - Australian Open organisers insisted on Thursday their COVID-19 protocols have been "really successful" despite some top players pointing to lax testing at the first Grand Slam of 2022.

Frenchman Ugo Humbert has tested positive and world number three Alexander Zverev of Germany believes there is probably more contagion going undetected.