FILE - In this Jan. 28, 2017, file photo, Serena Williams holds up a finger and her trophy after defeating her sister, Venus, in the women's singles final at the Australian Open tennis championships in Melbourne, Australia. Serena Williams is briefly back at No. 1 in the WTA rankings, despite not having played a match since January, and with plans to take the rest of 2017 off because she is expecting a baby. Thanks to a calendar quirk, Williams moved up one spot from No. 2, swapping places with Angelique Kerber. (AP Photo/Aaron Favila, File)