here is robert lipsitz in the "new york times" muhammad ali the three-time world heavyweight boxing champion who helped define his turbulent times as the most charismatic and controversial sports figure of the 20th century died on friday. he was 74 years old. as i was saying earlier this evening, our friend matt lauer had the great luck and good fortune in life to have been a friend of muhammad ali and remained a friend later in life. matt was close, as well to members of the ali extended family. and tonight, for us, matt lauer has a look back. >> i am the king of the world. >> hold it, hold it, hold it. >> i'm a mad man. >> he called himself the greatest. he was both adored and at times scorned. >> he had a lot of threats against him. >> but with superior skill and a unique style of boxing. >> float like a butterfly and sting like a bee. >> -- muhammad ali became a cultural icon. >> i'm so great. i'm so great. >> angelo dundee, ali's trainer and corner man for 21 years passed weighed in 2012 but was with ali during some of his most memorable fights. >> all you had to do was put a mike in hi