(9) Samantha Stosur vs. (3) Victoria Azarenka
Head-to-head: Azarenka leads 7-0

Clay can bring out clarity in Stosur and uncertainty in Azarenka, but Vika has dominated this match-up, winning 14 of the 15 sets they’ve played—all on hard courts—invoking her significant advantage on the backhand side. Azarenka has used her two-hander to pound away at Stosur’s sometimes erratic backhand. On hard court, Vika has driven her backhand down the line at times to exploit Stosur’s habit of running around the backhand to hit the forehand.

Clay should help Stosur's cause. It gives her more time to set up for her favored forehand, Azarenka is not as sure-footed on the dirt and 2010 French Open finalist Stosur can use her heavy topspin to open the court. Stosur has been prone to nerves, but she was very tough coming back from a break down in the first set and then shaking off an unsteady second set to defeat Petra Kvitova today.

The last time they met, Azarenka squeezed out a dramatic, 6-1, 4-6, 7-6 (5) victory to reach her first U.S. Open semifinal in a thriller. This surface should suit Sam, who will be primed to break through and beat Vika for the first time. But I’m riding with Azarenka.

The Pick: Azarenka in three sets

(2) Roger Federer vs. Jerzy Janowicz
Head-to-head: First meeting

Street artists atop Montemarte may soon be painting portraits of Janowicz, who peaked in Paris last year and has flattened a pair of Top 10-ranked Frenchman in succession this week. The day after the 6’8” Pole swept eighth-ranked Jo-Wilfried Tsonga, he rallied for a three-set win over ninth-ranked Richard Gasquet. Janowicz hit 19 aces and dropped serve twice in those two victories.

Janowicz is a confidence player who is in a pretty good groove on serve. When that happens, the rest of his game seems to flow. Look for him to hit his kick serve out wide to Federer’s one-handed backhand on the ad side. He will try to take the first strike, he loves the drop shot and is willing to play it from almost any position on the court and figures to be fired up for his first shot at Federer.

Federer showed the entire shot spectrum in schooling Gilles Simon today — he was commanding on serve, rapped his running forehand with authority, befuddled Simon with the drop shot so thoroughly he even hit a drop shot return winner — and if he brings that form to this match I cannot envision him faltering. Janowicz represents an entirely different challenge than the counter-punching Simon in that he can dictate on serve, but Federer looked sensational today.

The Pick: Federer in two sets

(7) Sara Errani vs. (2) Maria Sharapova
Head-to-head: Sharapova leads 4-0

A rematch of the 2012 French Open final pits Sharapova’s baseline aggression against Errani’s counter-strike skills. The energetic Errani has already given Italian fans something to celebrate: By reaching the Rome quarterfinals she will rise to a career-high rank of No. 5 on Monday, joining Francesca Schiavone as the second Italian women to crack the Top 5. The 5’4” Italian is more than a spin doctor with strong legs and titanium-strength competitive spine: Errani is an accomplished doubles player whose reached the doubles semifinals and is not afraid to finish in the front court.

The longer the exchanges last, the more it favors Errani. She is quicker around the court and will want to try to use her spins and angles to stretch Sharapova and get the sometimes boisterous Rome crowd involved. In contrast, the reigning Rome and Roland Garros champion will want to make this a straight-forward match. Sharapova isn’t into the concept of the rally as a negotiation: She will want to impose her superior power and depth to blast Errani back behind the baseline.

Ultimately, I believe Sharapova is too strong commanding the center of the court and controlling rallies from the first strike. She has reached four consecutive finals, hit the ball beautifully on the run vs. Sloane Stephens today and I believe she moves on to the semifinals here.

The Pick: Sharapova in two sets

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