(Adds details) By Martyn Herman RIO DE JANEIRO, Aug 13 (Reuters) - Britain crushed their American rivals to win the women's track cycling pursuit title in another world record time as the two fastest teams locked horns for gold at the Olympics on Saturday with the expected close battle ending in a romp. After trailing early on, the quartet of Laura Trott, Katie Archibald, Elinor Barker and Joanna Rowsell-Shand cranked up the pace to devastating effect, winning in 4:10.236 -- nearly two seconds quicker than the world record they set in the heats. Sarah Hammer's U.S. team had thrown down the gauntlet with a world record of their own in the morning heats only to see Britain respond almost immediately. More...