Australia’s out tennis star Samantha Stosur marked the 10th anniversary of her US Open singles title win with a women’s doubles crown at the US Open championships with her Chinese partner Zhang Shuai. Thirty-seven-year-old Stosur and Shuai (32), defeated teen sensations Coco Gauff and Caty McNally 6-3 3-6 6-3 on Sunday in an exciting women’s doubles final at Flushing Meadow. “We were playing against a couple of youngsters who even though they’re so young, have got quite a bit of experience, they