The Tokyo Olympics, which has been postponed to 2021, could be delayed further if coronavirus vaccine isn't found by then.
That's according to the head of the Japan Medical Association, Yoshitake Yokokura, who pointed out that it will be "difficult" to hold the games "unless effective vaccines are developed".
"I hope vaccines and drugs will be developed as soon as possible," he told a video press conference Tuesday in Tokyo.
Despite decline in daily new cases, Yokokura pointed out that Japan's coronavirus testing is still not sufficient.
It comes as several health experts raised similar concerns about hosting the games next July.
Last week, Kentaro Iwata, a specialist in infectious diseases, said he thought it “unlikely” that Japan will be ready by next summer.
Al Ain crushed 10-man Yokohama F Marinos 5-1 in the second leg of the Asian Champions League final on Saturday to register a 6-3 aggregate win and their first continental title in 21 years.
Fourteen-time French Open champion Rafa Nadal said there was still a chance this year's tournament in Paris may not be his last in comments ahead of his tough opener against fourth seed Alexander Zverev.
Outgoing Barcelona manager Xavi Hernandez said he was proud of his achievements with the club and was looking forward to being a fan again as he prepares to coach his final game against Sevilla.
World number one Novak Djokovic does not consider himself a favourite ahead of his title defence at the French Open, which begins with a first-round match against local hope Pierre-Hugues Herbert on Sunday.