RIO DE JANEIRO, Aug 16 (Reuters) - Defending champion Laura Trott took command of the women's track cycling omnium event at the Rio Games on Monday to close in on the fourth Olympic gold medal of her career. The 24-year-old finished second in the scratch race before winning the individual pursuit and elimination events. With three more disciplines scheduled for Tuesday, the British rider is eight points ahead of Belgium's Jolien D'Hoore and 10 ahead of American Sarah Hammer. ... More...