The Red Bulls fired American coach Chris Armas last month and South African Bradley Carnell took over as interim coach.
Yang, Li Yueru and Li Yuan combined for 12 points, while Guo Zixuan made Hebei's only basket during the span.
Next up for the 33-year-old is Russia's world No. 16 Karen Khachanov. Djokovic owns a 3-1 lead in the head-to-head record against Khachanov but the latter won the pair's previous encounter in Paris - at the 2018 Paris Masters when the Russian claimed a straight-set win in the final to clinch the biggest title of his career until now.
Despite its backcourt duo of Chen Yanyu and Chen Xinlei's lackluster performance, Shaanxi can still find positives as sophomore Yu Jiarui posted a career-high 35 points.
"We didn't perform well in the first quarter. We had a tough start, but ultimately took our chance," Shaanxi coach Jiang E'Ying reflected.
"The match today I think we both play really well and a really great match. She played unbelievably good," said Zhang, who defeated Burel 6-3, 7-6(3) in the Strasbourg Open before coming to Paris.
"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.
Raheem Sterling opened the scoring for the visitors in the 17th minute, but Rodrigo Moreno's first goal for Leeds in the 59th minute, following an error from City keeper Ederson, gave his side a point they more than deserved.
Shanghai guard Peng Szu-Chin hobbled off the court, seemingly through a strain, just one minute into the second half. Without one of its main scorers, Shanghai could not catch up on the offensive end as Xinjiang pulled away through backcourt combo Wang Siyu and Wang Lili's efforts.
Tuchel's side have been drawn with Manchester United, Istanbul Basaksehir and RB Leipzig in this season's UEFA Champions League group stage.
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.