Olympics-Cycling-Briton Trott defends omnium to win fourth gold

(Adds details, quotes) By Martyn Herman RIO DE JANEIRO, Aug 16 (Reuters) - Britain's Laura Trott won her fourth Olympic gold medal with a masterful ride in the track cycling omnium on Tuesday, leaving her rivals scrapping for podium places. Trott, the first British woman to claim three Olympic golds when leading the team pursuit home last week, held a commanding lead going into the points race, the sixth discipline of the event, and turned it into a procession. As the 24-year-old ticked off the 100 laps without incident, picking up early sprint points for insurance, the real battle was for silver between American veteran Sarah Hammer and Belgium's Jolien D'Hoore. Hammer finished runner-up, as she did in London four years ago, while D'Hoore had to settle for bronze. Trott won three of the six disciplines throughout two dominant days on the Rio boards. On Monday she was victorious in the individual pursuit and elimination events and she went quickest on the penultimate discipline, the flying lap, on Tuesday to move 24 points ahead. After crossing the line, still 24 points in front of Hammer, she headed for the seats populated by a noisy British element, grabbing a flag emblazoned with the words "Go Trotty Go". "I can't believe I've got four," she said, fighting back the tears. "I didn't expect that at all, that it all came together. Trott, fiance of team mate Jason Kenny, who was going for a sixth Olympic gold later in the keirin, has now won every Olympic race she has entered, having claimed gold in the team pursuit and omnium at London 2012. (Editing by Ed Osmond)