Alysa Liu became the first American women's figure skating world champion in nearly two decades Friday night, dethroning three-time defending champion Kaori Sakamoto with a brilliant free skate that earned her a standing ovation inside TD Garden.

Team USA's Alysa Liu was nearly flawless in her short program to take the lead. Isabeau Levito and Amber Glenn also qualified for the long program.

In a stunning return to the sport, Alysa Liu became the first American woman to win a world championship in 19 years in Boston on Friday.