See main article: article and 2009 US Open (tennis).
Serena and Venus Williams defeated the defending champions Cara Black and Liezel Huber in the final, 6–2, 6–2 to win the women's doubles tennis title at the 2009 US Open. It was their second US Open title together and tenth major title together overall. It was the second component in an eventual non-calendar-year Grand Slam for the sisters. [1]