The 8th seed and the six-time US Open champion Serena Williams is through to her 16th quarter-final in New York following a 6-3, 6-4 win over Petra Martic in an hour and 31 minutes. The American twisted ankle at 2-2 in the second set but luckily for her the injury wasn't that serious, staying on the court and finishing the job to advance into the last eight, never losing before the quarters after 2006!
Serena lost just 18 points in her games, fending off two out of three break chances and mounting the pressure on Martic with 37 winners and 19 unforced errors on her tally. The Croat gave her best to stay in touch altough there was nothing she could do against the aggression of her rival, facing eight points and giving Williams three breaks, enough to hit the exit door.
From 40-0 down, Petra grabbed five straight points for a break in the first game of the match, staying in front only for a couple of minutes as Serena broke back in game two with a forehand down the line winner. Williams had the upper hand in the rest of the set, taking four straight points on the return in game eight to score a break following a backhand winner, saving two break chances in the next game to close the set after a drop shot winner for a 6-3 in 44 minutes.
Overcoming that injury, Serena broke in the fifth game of the second set with a volley winner, squandering four opportunities for an even bigger lead in game seven before closing the encounter with an ace in game ten to advance and set the clash against Qiang Wang who defeated Ashleigh Barty.