Serena Williams needed just 58 minutes to beat fellow American Sloane Stephens 6-4, 6-0 on Tuesday and reach the third round of the Madrid Open.
The top-ranked Williams broke Stephens four times and saved both break points she faced to secure her 25th straight win. She will next face the winner between Victoria Azarenka and Ajla Tomljanovic.
“She’s such a tough player,” Williams said of Stephens. “I’ve never won a 6-0 set against her before, and I don’t think I can ever do that again.”
Williams remained undefeated in 2015, with her last loss coming in round-robin play at last year’s WTA finals. Earlier, Caroline Wozniacki powered past Christina McHale of the United States 7-5, 6-0. The fifth-seeded Wozniacki hit five aces and committed fewer unforced errors on the red clay to beat the 22-year-old player from Teaneck, New Jersey in 1 hour, 30 minutes. Wozniacki will face Agnieszka Radwanska after she eased past Casey Dellacqua 6-2, 6-1.
Maria Sharapova advanced to the third round of the Madrid Open by beating Mariana Duque-Marino of Colombia 6-1, 6-2. The Russian broke Duque-Marino’s serve four times while saving three break points on her own serve.