BEIJING — Coco Gauff won her second title this season with a lopsided 6-1, 6-3 victory over Karolina Muchova in the final of the China Open on Sunday. Aged 20, the sixth-ranked U.S. player became the youngest China Open champion in 14 years. She is also the second American champion in Beijing, following Serena Williams’ title runs in 2004 and 2013. [time-brightcove not-tgx=”true”] It was Gauff’s eighth career title.