On this day in 1950, Althea Gibson broke the color barrier in tennis and became the first African-American player to compete at the U.S. National Championships, the precursor of today's U.S. Open. Gibson defeated Barbara Knapp in her debut but lost in the second round to American Louise Brough Clapp, who had won the previous three Wimbledon titles. The following year, Gibson became the first black player to compete at Wimbledon. In 1956, Gibson became the first black player to win the French championships. In 1957, she made more history by winning Wimbledon and the U.S. Nationals, the first black player to win either. She repeated that feat in 1958. Gibson, who died on Sept. 28, 2003 at the age of 76, won 11 Grand Slam titles (including doubles) in all. Last week, the U.S. Postal Service honored Gibson with a commemorative stamp in its Black Heritage series.