Errani looks for upset over Serena at the US Open

Serena Williams, Maria Sharapova and Victoria Azarenka have a lot in common: Big serves, big games and one Grand Slam title apiece in 2012.

Then, there is the fourth semifinalist at the U.S. Open, Sara Errani.

The 25-year-old Italian is 5-foot-4 (1.63 meters), spins serves in at an average speed of around 80 mph (128 kph) and yet, somehow, keeps getting her name in the conversation at the biggest events in tennis.

A runner-up at the French Open, 10th-seeded Errani has vaulted 35 spots in the rankings this year, debunking the thought that only power players with power games can succeed at the highest level.

On Friday, Errani plays No. 4 Williams in one semifinal, with top-seeded Azarenka meeting No. 3 Sharapova in the other. The winners play for the title on Saturday.