Ligety already had won the super-combined and super-G titles by the time he blitzed the field in the giant slalom his speciality by 0.81 seconds in Schladming, Austria.
The victory gave the 28-year-old Ligety his fourth career world title, and established him as one of the favorites in everything but the downhill at the 2014 Sochi Olympics in Russia less than a year from now.
No matter what, Ligety already must surely rank among the best skiers in American history.
Ligety has a gold medal in the combined at the 2006 Turin Olympics in Italy, along with 34 medals and 15 victories on the World Cup tour. He has equalled Bode Miller's career record of four world championships, and is the first person man or woman to win the super-G, super-combined and giant slalom.
He's also just the sixth man to win back-to-back giant slalom titles.
"This has been a crazy, unbelievable week," Ligety said. "Definitely far exceeded my expectations."
Ligety carved a nearly perfect first run to take a commanding lead of 1.30 seconds over Norway's Aksal Lund Svindal, and he easily held on over a second run that saw Austria's Marcel Hirscher and Italy's Manfred Moelgg overtake Svindal for the silver and bronze medals.
Ligety finished with a two-run combined time of 2:28.92, while Hirscher clocked 2:29.73 and Italy's Manfred Moelgg finished in 2:30.67 for third.
"Marcel has been really pushing me the last couple years in GS," Ligety said. "He's been a big motivator to continue the level of training and pushing as hard as I do. It's not easy having such a young guy like that be so, so good at such a young age. I've had to push really hard and he's pushed me to a new level."
Only four other men have ever won three or more medals at a single world championships, including France's Killy in 1968 and Emile Allais in 1937, Norway's Stein Ericksen in 1954 and Austria's Toni Sailer in 1956 and 1958.
"To win three gold meals here is awesome," Ligety said, "and to join some of the legends of the sport. There was definitely a lot of pressure coming into the GS as the defending champion. With those gold medals, it definitely added a lot of extra pressure."
Not that you could ever tell.
Watch Ligety win
O Ted Ligety's record-setting win Friday in the giant slalom at the FIS Alpine World Ski Championships is online at sltrib.com/sports.