Djokovic, a 34-year-old from Serbia who is ranked No. 1, is now 24-0 in the sport’s four most important events this season, having won the Australian Open in February, the French Open in June and Wimbledon in July. The last man to go 4 for 4 at the majors was Rod Laver in 1969; Steffi Graf was the last woman, in 1988.
