LONDON (AP) — Serena and Venus Williams won the women’s doubles tennis title and Tiki Gelana of Ethiopia held off her two closest rivals to win a rainy women’s marathon today at the London Olympics.

The Williams sisters became the first tennis players to win four Olympic gold medals, defending their Beijing 2008 doubles title with a 6-4, 6-4 victory over Andrea Hlavackova and Lucie Hradecka of the Czech Republic.

Serena made it a perfect Olympics, playing under the roof on a rainy afternoon at the All England Club a day after she dominated Maria Sharapova 6-0, 6-1 for singles gold. She joined Steffi Graf as the only women to complete the Golden Slam — winning the Olympics and the four majors.

In the marathon, which started and ended at Buckingham Palace, Gelana finished in a time of 2 hours, 23.07 seconds, holding off Priscah Jeptoo of Kenya by five seconds. Tatyana Petrova Arkhipova of Russia took the bronze.