Mainz failed to put up any resistance while Union relentlessly tripled their lead after Marvin Friedrich headed home Christopher Trimmel's free-kick in the 63rd minute for 3-0.
Palmeiras has not lost since a 1-0 defeat to Corinthians in the Sao Paulo state championship on July 22.
On the other hand, Michalovce and Nitra are leading the rankings after two victories in succession. Kosice, Nove Zamky, and the Hungarian team Miskolc are still in quarantine.
Chaux, who was named in Colombia's preliminary squad for last year's Copa America in Brazil, joined America de Cali this year from their Colombian top flight rivals Patriotas Boyaca.
Once again Getafe is off to an excellent start to the season and although its style of football is not always attractive to watch, it is effective as it showed against Betis in midweek.
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.
Four naturalized players Jiang Guangtai, Fei Nanduo, Ai Kesen and Li Ke were called up. Wu Xinghan from Shandong Luneng replaced Wuhan Zall midfielder Liu Yun who misses out due to injury.
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.
Despite the host's dominance they had to be patient as Schalke was able to neutralize the attacks in the opening period.
It is Athletic Bilbao's first signing since January 2019.
Rafael Nadal hits a return during the men's singles third round match against Italian Stefano Travaglia at French Open in Paris on Oct. 2, 2020. (Photo by Aurelien Morissard/Xinhua)