Then in the third set, Williams was rarely troubled by her rival en route to victory.
Things nearly got a lot worse for Zall before going off at half-time, when the ever-lively Zhang broke free once again, but this time his shot was well saved by the goalpost.
Liang Ruiji and Li Jingmin from Guangdong finished first and second respectively in the individual dressage race, and Penpa Tsering from Tibet came third.
The 33-year-old striker announced his "U-turn" 11 days after informing the club that he wanted to leave this summer and arguing that a clause in his contract meant he could leave for free.
Williams defeated Russia's Margarita Gasparyan 6-2, 6-4 while Kenin needed an hour and 22 minutes to maneuver past Canadian youngster Leylah Fernandez 6-4, 6-3.
Both World Cups and the Finals will be staged in China with support from the Chinese Table Tennis Association (CTTA), meaning that the Women's and Men's World Cups will no longer take place in Bangkok, Thailand, and Dusseldorf, Germany as originally planned.
"It was a tough match and we fought hard. It wasn't easy, it could be better in the future," Mbappe said. "The most important thing is the result."
Pepe has made 99 appearances for Gremio and scored 21 goals since making his professional debut in 2017.
The teams are due to meet at Estadio Azteca in Mexico City on September 30, however health concerns and possible quarantine measures have cast doubt over the fixture.
"In the end I did my thing and tried to stay with the best guys, and here we are," said the Mitchelton-Scott rider.
The 23-year-old, who has previously been linked to interest from Spanish giants, Real Madrid and FC Barcelona, has agreed a contract until June 2025. He will travel to Manchester to join his new teammates after the Netherlands' UEFA Nations League game against Italy on September 7.