Rio de Janeiro - Venus Williams missed out on her chance to become the first tennis player to win five Olympic gold medals when she and partner Rajeev Ram were defeated in the mixed doubles final on Sunday.
They lost 6-7 (3/7), 6-1, 10-7 to US compatriots Bethanie Mattek-Sands and Jack Sock.
Venus won singles gold at Sydney in 2000 and doubles titles with sister Serena in 2000, 2008 and 2012. She and 32-year-old Ram had never played together before Rio.
Ram was a late call-up to the US squad after 2012 men's doubles champions Bob and Mike Bryan pulled out for health reasons.
Earlier on Sunday, Lucie Hradecka and Radek Stepanek of the Czech Republic needed just 71 minutes to claim bronze, defeating India's Sania Mirza and Rohan Bopanna 6-1, 7-5.
Olympic tennis results on Sunday:
Men
Bronze medal match
Kei Nishikori (JPN) bt Rafael Nadal (ESP) 6-2, 6-7 (1/7), 6-3
Mixed doubles
Gold medal final
Bethanie Mattek-Sands/Jack Sock (USA) bt Venus Williams/Rajeev Ram (USA) 6-7 (3/7), 6-1
Bronze medal match
Lucie Hradecka/Radek Stepanek (CZE) bt Sania Mirza/Rohan Bopanna (IND) 6-1, 7-5