Caroline Wozniacki has taken a swipe at ex-fiancee Rory McIlroy - by wearing a pair of high heels. The former world No 1 posted a picture of herself shopping with a friend in Istanbul where she is competing in the Istanbul Cup. Wozniacki said: 'Out and about in Istanbul. It's been three years since I have worn high heels on a normal day out. #feelsgood #looksgood #shopping #highheels #sun.' She later deleted the post on Instagram.