Fiorentina loanee Pedro put the hosts ahead with a low strike before Bruno Henrique converted from the penalty spot after a Leo Gomes handball.
Gaston is to challenge third seed Dominic Thiem in the fourth round. Earlier in the day, the Austrian had claimed another straight-sets victory over 28th seed Casper Ruud, beating the Norwegian 6-4, 6-3, 6-1.
Burel wasted three set points when she took a 5-3 lead in the first set and stormed to 40-0 in the ninth game. But Zhang battled back to save all three, and held the serve before breaking Burel's in the tenth to level the score at 5-5.
Hertha responded well and shocked the Bavarians with the equalizer as new arrival Jessic Ngankam scored his debut goal one minute after his substitution.
Wang Lili made 11 of 20 field shots and scored 25 points for Xinjiang, one of the title contenders over the current campaign. Wang Siyu helped with 11.
"We showed our character," Jiangsu coach Ding Tie said. "But after some young players substituted in, the level of our defense went down."
"I'm very happy. It was a great match, I didn't make any mistakes. Casper is a really great player, very attractive to play, I think there were many good rallies, it was a good match from both of us," said the recently-crowned US Open champion.
According to the schedule, except for the training on Sunday afternoon, all the other sessions will be arranged in the morning from October 5 to 9.
"If you win 4-0, you have to be happy. We will analyse today's game in a couple of days but for now we are delighted. Today it was important to be effective when it mattered most," Union head coach Urs Fischer said.
Bierhoff demanded successful games to strengthen team spirit and fan identification. The 1996 European Champion said a real lift in mood is needed to travel down the road to the 2021 European Championship. Enditem
It is the second time for Ziyuan County to hold such an international race, the route of which covers several 4A-level scenic spots.