Jannik Sinner retires with cramp to give Griekspoor victory at Shanghai Masters

Heat and humidity forces Italian out in third setAmanda Anisimova wins China Open in BeijingJannik Sinner was forced to retire from his third-round match at the Shanghai Masters against Tallon Griekspoor, the 27th seed, after suffering from cramps in humid conditions while trailing the Dutchman 6-7 (3), 7-5, 3-2 on.In the final weeks of a long, arduous season for all, the conditions in Shanghai have been severe this past week, particularly on Sunday as players tried to compete in 90% humidity. M...