The youngest UFC Champion Jon Bones Jones . Im all against PEDs but there have been a lot of guys who used PEDs but got their ass whooped and lost so many times . If you count Jones loss vs Hamill as a loss then you should never watch mma again . DC 2x Gus Rampage Sonnen (Who gave anderson absolute hell tapped rua and got merked by Jones inside one round) Machida Rashad Teixeira TRT Belfort Rua Bader So when you talk about undefeated fighter dont bring up fighters with padded records . Jon Jones stayed undefeated inside the octagon while never facing easy competition .