Serena Williams entered Tuesday's quarterfinal against Victoria Azarenka at Wimbledon as the favorite and duly progressed. Shaun Botterill/Getty Images But once again she had to rally. Azarenka, a former No. 1 who had Williams in trouble at the French Open, claimed the opening set in London. Ian Walton/Getty Images But Azarenka, facing a determined Williams, couldn't match the American as the encounter developed. Ian Walton/Getty Images Indeed Williams jumped out to a 3-0 lead in the third set and wouldn't look back. It would turn out to be that kind of day for Azarenka. Shaun Botterill/Getty Images) Williams jumped in joy when it was over. She's now two matches away from winning four grand slams in a row -- or the "Serena Slam." JUSTIN TALLIS/AFP/Getty Images Williams next faces Maria Sharapova, who was a three-set winner over American CoCo Vandeweghe. Sharapova has lost 16 in a row to Williams. GLYN KIRK/AFP/Getty Images Vandeweghe, whose uncle Kiki played in the NBA, got the crowd off their feet with her shot-making. She accused Sharapova of gamesmanship. GLYN KIRK/AFP/Getty Images) Vandeweghe's fellow young American, Madison Keys, faced Agnieszka Radwanska in another quarterfinal. Julian Finney/Getty Images And it was the 2012 finalist who prevailed. It's been a tough season for Radwanska, so the victory was much needed. Clive Brunskill/Getty Images Garbine Muguruza, seen here, beat Timea Bacsinszky and plays Radwanska on Thursday. The Spaniard upset Williams at the French Open last year. Clive Brunskill/Getty Images Prev Next