BEIJING — Dawn Harper of the U.S. wins the gold medal in the women’s 100-meter hurdles.

Harper won in a personal best 12.54 seconds Tuesday after U.S. teammate Lolo Jones, who had a clear lead, was knocked off balance when she hit the next-to-last hurdle.

Australia’s Sally McLennan got the silver medal in a photo finish; both she and Canada’s Priscilla Lopes-Schliep crossed in 12.64, but when the time was extended to thousandths of a second, it showed McLennan was faster.

Jones, the world indoor champion who had the season-leading time going into the final, finished seventh in 12.72.