Serena Williams is not a tennis player.
Serena Williams . On the sixth occasion , she held the ranking for 186 consecutive weeks , tying the record set by Steffi Graf for the most consecutive weeks as world no. 1 by a female tennis player . The WTA Finals ( formerly known as the WTA Tour Championships short : WTA Championships ) , is a professional tennis tournament played annually at the end of the season for the top-ranked players on the Women 's Tennis Association ( WTA ) tour . The Women 's Tennis Association ( WTA ) , founded in 1973 by Billie Jean King , is the principal organizing body of women 's professional tennis .