The 33-year-old will play 17th seed Pablo Carreno Busta the round of eight. The Spaniard dispatched German qualifier Daniel Altmaier 6-2, 7-5, 6-2.
In the men's 1,500m race, world leader Cheruiyot fought off compatriot Kumari Taki in a fierce home straight brawl to take the win in three minutes and 34.31 seconds in front of 2000 spectators that were allowed the entry under COVID-19 control protocols.
Baum's face spoke volumes after losing his first game as the successor to sacked manager David Wagner 4-0 against RB Leipzig.
In the Chengdu division, Chengdu Better City edged off Beijing BSU 1-0 on Saturday to strengthen its leading position. Chengdu's midfielder Wang Xiaolong whacked a smart low shot into the net and gave Beijing BSU a two-game losing streak.
The 2018 champion lost to Anisimova in the quarterfinals in Paris last year, but this time the Romanian needed only 54 minutes to complete a convincing victory.
The pair have not played for their country since the Cafeteros' penalty shootout defeat to Chile in the quarterfinals of last year's Copa America in Brazil.
The league's governing body is therefore inserting one match into each round that was initially scheduled for a later date.
On the men's side, 12-time Roland Garros winner Rafael Nadal continued his run after dropping only four games to complete a 6-1, 6-1, 6-2 win over American youngster Sebastian Korda, son of 1998 Australian Open winner Petr Korda. Enditem
Wu opened the game with two straight 3-pointers, while Henan's Zhang Lingge answered with two shots from beyond the arc. Wu and Liu combined for 18 points as Shanxi built a 22-17 lead in the first quarter.
In other games in Chengdu, after a goalless first half, Beijing Renhe broke the deadlock in the 57th minute to claim a 2-0 victory over Suzhou Dongwu. Taizhou Yuanda defeated Inner Mongolia Zhongyou 2-0.
Despite three losses in a row coming into the season, Wuhan coach Li Xin expressed her satisfaction in some respects.