UFC history is made as three undefeated athletes trade the Olympics for the Octagon. In the main event, dominant bantamweight champion Ronda Rousey, an Olympic bronze medalist in judo, seeks to defend her title against Sara McMann, an Olympic silver medalist in wrestling. Plus, former Team USA captain Daniel Cormier makes his long-awaited light heavyweight debut, and three key welterweight bouts reshape the division's rankings. Rory MacDonald meets Demian Maia, Mike Pyle faces TJ Waldburger and Stephen Wonderboy Thompson takes on The Ultimate Fighter: The Smashes winner Robert Whittaker.Special Features: Countdown to UFC 170, weigh-in show and Post-Fight Press Conference