Real Madrid kept pressing, but Real Sociedad always gave the sensation of danger on the break with winger Ander Barrenetxea a precocious talent on the left.
Roberto Lopez sealed the win in the 94th minute with a powerful shot into the corner after another assist from the impressive Merino.
The organizers will also establish working teams for each test event and for venue operation, with detailed plans for accomodation, catering, medical service, transportation and volunteers.
Saturday ends with a difficult test for Real Madrid as they visit a Betis side under the guidance of former Madrid coach Manuel Pellegrini.
Cazares, capped 21 times for Ecuador, has made 205 appearances and scored 41 goals for Atletico Mineiro since joining the Belo Horizonte outfit from Argentina's Banfield in 2016.
"The relationship with the players is excellent, it is important to have a dialogue with them," the 41-year old added.
But discussions between the government and the Grand Slam organizers were ongoing as to how this policy would affect Roland Garros, which has been scheduled from September 27 to October 11.
Andreescu, the 2019 US Open champion, missed the opening months of the year because of a knee injury before the pandemic forced the suspension of the sport.
He didn't play in Real Sociedad's game against Real Madrid on Sunday night in order to ensure he was not injured ahead of the move.
Yet, the fourth set became Jiangsu's one-sided show again as Gong Xiangyu made six kills and one block.
After Beijing jumped to a 13-4 lead in the third set, Yunan called a time-out, closing it to one point at 20-21, and called another time-out but failed to level it even.