Iga Swiatek was accused of being “insincere” by Danielle Collins after a stormy Olympics clash in which the Pole was left struggling to breathe after being felled by a pile-driver backhand by the powerful American. In a tense quarter-final, Collins retired at 1-4 down in the final set having left the court for a medical timeout. When the pair shook hands at the net, the 30-year-old Collins exchanged heated words with a bewildered Swiatek. “I told Iga she didn’t have to be insincere about my injury. I haven’t had the best experience and I don’t really feel like anybody needs to be insincere,” said Collins, without elaborating.