Updated

Top-ranked lightweight Katie Taylor rode a dazzling swell of Irish fan support to a 26-15 victory over Britain's Natasha Jonas on Monday in the quarterfinals of the first Olympic women's boxing tournament.

Flyweight Marlen Esparza and middleweight Claressa Shields also clinched the U.S. team's first two boxing medals in London with impressive victories. Esparza patiently outboxed Venezuela's Karlha Magliocco, and the 17-year-old Shields closed impressively in a win over Swedish veteran Anna Laurell.

Women's boxing pioneer Mary Kom of India and Britain's Nicola Adams also secured medals in this brisk tournament, which only began Sunday with the historic first bouts.

Top-seeded British middleweight Savannah Marshall was upset by Kazakhstan's Marina Volnova, Shields' next opponent.