NEW YORK (AP) — Serena Williams was the first black woman since Althea Gibson to win the US Open. Venus Williams was the first black woman since Gibson to win Wimbledon.

Fittingly, both of the Williams sisters' first-round matches at this year's US Open have been scheduled for Monday night at Arthur Ashe Stadium — right after a tribute marking the 50th anniversary of Gibson's first Grand Slam singles title.

The back-to-back Williams matches under the lights on the tournament's first day were to be announced by the US Tennis Association yesterday. The No. 8-seeded Serena Williams will play Angelique Kerber of Germany, while No. 12 Venus Williams was drawn to face a qualifier.

In 1950, Gibson became the first black man or woman to play in the US National Championships, the tournament that became the US Open. She won the event in 1957 and 1958 for two of her five Grand Slam singles titles.

Gibson also broke the colour barrier at Wimbledon, which she won in 1957 and 1958, and on the LPGA Tour.

When Gibson died in 2003, Venus Williams said: "I am grateful to Althea Gibson for having the strength and courage to break through the racial barriers in tennis. Her accomplishments set the stage for my success, and through players like myself, Serena, and many others to come, her legacy will live on."