View Photo Gallery: Tyrieshia and Antoine Douglas are only brother-sister combo to qualify for Olympic boxing trials.

The District’s Tyrieshia Douglas won convincingly Monday on the opening night of the first U.S. Olympic women’s boxing trials , taking an early step toward qualifying for the U.S. Olympic team that will compete in London.

With a 34-11 victory in the flyweight division over Latonya King, Douglas, a two-time U.S. champion, remains in the winners’ bracket at the week-long trials in Airway Heights, Wash. She will face 2011 Pan American Games representative Christina Cruz Tuesday night following Cruz’s 15-12 win over Virginia Fuchs.

No other local women won their opening bouts.

Baltimore’s Franchon Crews fell, 31-19, Claressa Shields, a 16-year-old up-and-coming middleweight from Flint, Mich. Alexandria’s Dara Shen, a late entrant, lost 34-9 in her opener to welterweight world champion Andrecia Wasson; and the District’s Asia Stevenson fell to N’yteeyah Sherman, 42-17, in the lightweight class despite taking an early lead. All remain alive in the hunt for Olympic slots, but will have to climb from the losers’ bracket.

Twenty-three women are competing in the event. Women’s boxing will appear on the Olympic program for the first time at the London Summer Games.