Day 11 of the 2015 US Open Semis. #usopen2015

Day 11 of the 2015 US Open finds four of the best in the women’s game still standing, as each continues her quest to stand alone. 
The final four who’ve played their way into the penultimate round of this Flushing fortnight represent an intriguing mix, pitting the top two seeds against two tough and talented Italians. No. 1 seed Serena Williams takes on the unseeded Roberta Vinci, while second seed Simona Halep squares off with the No. 26 Flavia Pennetta. 

Two matches removed from tennis’ toughest title, each of Thursday’s competitors will be redoubling her efforts as she looks to advance to this tournament’s second Saturday. To get there, each will need to be semi-tough.

It pretty much goes without saying that no one has been tougher this season on the game’s biggest stages than Williams, who now stands just two matches removed from the most historic happening of her sure-fire Hall of Fame career – capturing the Grand Slam. Winning all four majors in a calendar year is the rarest of feats in tennis, accomplished only six times by five different players in the history of the sport.