Martina Navratilova remains on course to equal Billie Jean King's Wimbledon record of 20 titles.
The 46-year-old, who entered the Championships on 19 titles, combined with Leander Paes, of India, to reach the semi-finals of the mixed doubles with a 5-7 7-6 6-4 win over American pair Mike Bryan and Lisa Raymond.
The American, who has won nine singles titles at Wimbledon, had earlier suffered defeat in her record-breaking 300th match at the All England Club.
She and Russian teenager Svetlana Kuznetsova were beaten 4-6 6-2 6-4 in the women's doubles by Kim Clijsters and Ai Sugiyama.