"Additionally, several countries across the confederation have travel restrictions and quarantine requirements, which would make international football involving 30 national teams extremely difficult."
World number one Djokovic was stunningly disqualified after accidently hitting a line judge with a ball during his round of 16 clash with Pablo Carreno Busta of Spain.
"Right now I'm really focused on the US Open, and nothing else I can think about right now," said Williams, who won six of her 23 Grand Slam singles titles at the US Open.
Dejan Lovren scored first for the visitors in the 18th minute, but Antoine Griezmann's close-range effort and Dominik Livakovic's own goal gave France the lead before the interval.
In an earlier match, Shenzhen edged defending champion Zhejiang 3-2, with both teams of similar strength showing their best from the very beginning.
Two 1-1 draws against Spain and Switzerland showed that time might be running out, as no more than nine months are left complete the rejuvenation of the German team, including a new approach on the pitch.
"We have been informed that the AIU is going to organize a number of group testing sessions specifically for road runners. The sessions will be held at a number of locations across Kenya during September," the country's athletics running governing body Athletics Kenya said in a statement on Thursday.
After consultation with the International Paralympic Committee (IPC), Beijing 2022 redrew and recolored its Paralympics emblem "Flying High" to keep in line with the new Paralympic symbol "Agitos", and the words "PARALYMPIC GAMES" were removed from the original design.
After a discussion of around 10 minutes between tournament referees and officials, Djokovic was disqualified from the match in accordance with the rules.
Samir Memisevic (C) of Hebei China Fortune competes during the 9th round match between Hebei China Fortune and Shanghai SIPG at the postponed 2020 season Chinese Football Association Super League (CSL) Suzhou Division in Suzhou, east China's Jiangsu Province, Sept. 5, 2020. (Xinhua/Li Bo)
"He's a very solid player, maybe doesn't possess any big weapons, but every shot is very good," Djokovic said of Busta. "He returns a lot of balls, so I've got to be ready for a lot of exchanges. It's going to be a demanding match physically and mentally. Hopefully I'll be able to continue the good performance that I had tonight."