The outbreak follows Flamengo's week-long trip to Ecuador for a Copa Libertadores double-header against Independiente del Valle and Barcelona SC.
Newly-crowned US Open champion Dominic Thiem, who has lost back-to-back Roland Garros finals to Nadal, has been drawn into the same half as the Spaniard and faces non-seeded former world No. 3 Marin Cilic.
Real Madrid coach Zinedine Zidane was without Eden Hazard, Marco Asensio and Isco, but he produced a surprise by including Martin Odegaard, who spent last season on loan in San Sebastian, in his starting 11 and leaving Casemiro on the subs bench.
If head coach Domenec Torrent didn't have enough obstacles to overcome, an eruption of ash from the Sangay volcano left his team unable to train on Sunday.
With one round left, Chongqing has booked a berth in the next stage.
In the other match of Group C, Almoez Ali scored his third goal of the league to help Al Duhail SC beat Persepolis FC 1-0 and overtake the latter to lead the group.
Corinthians, one of Brazil's most successful and popular clubs, are currently 13th in the country's top flight standings with just three wins from 10 matches this season. Enditem
However, apart from pride and joy, other topics are seemingly keeping the Bavarian's coach Hansi Flick's mind busy. The 55-year-old is turning his thoughts to future challenges.
The 16-team CSL was split into two groups, with each group of eight teams based respectively in Dalian and Suzhou. Both groups will play 14 rounds in the first phase, which is to end next Monday.
Monday's first game saw Aston Villa beat Sheffield United 1-0 in Villa Park on a 63rd minute goal by Ezri Konsa Ngoyo.
The striker said that joining Atletico Madrid was an "attractive challenge" and that he had spoken to Antoine Griezmann and Uruguay international Diego Godin about the club.