Madrid Open WTA: Serena to face Sharapova in the final

Serena Williams' tactic of staying in her hotel room and being "boring" appears to be paying off after the world number one and top seed swept past Sara Errani into the final of the Madrid Open on Saturday.

Chasing a 50th career title at the clay event in the Spanish capital, defending champion Williams was far too strong for the Italian seventh seed, winning 7-5, 6-2 to set up a clash against Maria Sharapova, who bested Ana Ivanovic 6-4, 6-3.

The win over the Serb gave the Russian her 500th singles win, become the eighth active player and the 36th overall to achieve the feat.

American Williams, 31, whose interests away from tennis include fashion and acting, said she had been avoiding "too many extra-curricular activities" to prepare for her matches.

"I usually just stay in my room really and be the most boring person you can ever imagine," she told a news conference.

"That's kind of the way I get focused," she added.

Sunday's opponent will be a different proposition to Errani, with Russian Sharapova and Ivanovic of Serbia among the players on the Tour who can come close to matching Williams for power.

"I look forward to it," Williams said.

"I feel like this whole tournament I've only played clay court players from my first round to now.

"Everyone was also smaller than me. So I think tomorrow will be a really good match. Different game. More power obviously, but still a lot of the consistency."

World number two Sharapova will replace Williams at the top of the rankings if she goes on to win the final. For the Russian it will be her 50th WTA Final, the 26-year-old having won 29 of those.

Photograph: Gonzalo Arroyo Moreno/Getty Images