In rankings quirk, Serena back at No. 1

Serena Williams is briefly back at No. 1 in the WTA rankings,

despite not playing 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 Monday from No. 2, swapping places with Angelique Kerber. The reason: The women’s clay-court tournament being played this week in Germany was played a week earlier a year ago. Kerber lost the rankings points she earned there and can’t replace them until the end of this year’s tournament.