Villegas shot a 7-under 63 and finished at 17-under 263. He earned $954,000 and 500 FedEx Cup points in the final regular-season event.
The Colombian had four birdies and an eagle on the front nine, added a birdie on the par-5 15th and took the lead into the clubhouse. He then watched the rest of the field stumble late, giving him his fourth PGA Tour title and first since the 2010 Honda Classic.
Bill Haas and Freddie Jacobson tied for second. Haas had a 64, and Jacobson shot 66.
Jacobson needed a par on the final hole to force a playoff, but he rolled his 11-foot putt inches past the hole.
Inbee Park captures fifth major title at LPGA Championship
Inbee Park successfully defended her title in the LPGA Championship, beating Brittany Lincicome with a par on the first hole of a playoff to end the United States' major streak at three.
On the playoff hole on Monroe Golf Club's par-4 18th, Park hit her second into the rough behind the hole. Lincicome hit her approach to the left fringe, nearly identical to her position on the final hole of regulation when she made a bogey to fall in the playoff.
Lincicome chipped 6 feet past the hole and failed to convert for bogey. Park, the winner last year at Locust Hill in a playoff with Catriona Matthew, chipped to 3 feet and calmly sank her par putt for the victory.
Park finished with a 2-under 70 to match Lincicome at 11-under 276. Lincicome had a 71.
The South Korean player won her fifth major title and fourth in the last two seasons
Bernhard Langer posts fifth Champions Tour victory of year
Bernhard Langer rallied to win the Dick's Sporting Goods Open for his fifth victory of the year, while Kevin Sutherland followed his tour-record 59 with a 74 to drop into a tie for seventh.
The 56-year-old Langer closed with a bogey-free 66 for a one-stroke victory over Woody Austin and Mark O'Meara. Langer finished at 16-under 200 at En-Joie for his 23rd career victory on the 50-and-over tour.
Sutherland, the second-round leader, had five bogeys — four on the first 10 holes — and three birdies in the final round. Playing his third Champions Tour event since turning 50 in June, he finished at 12 under.
Austin had a 65, and O'Meara shot.
Gunn Yang wins U.S. Amateur title
South Korea's Gunn Yang has completed his improbable run to the U.S. Amateur title with a 2-and-1 victory over Canada's Corey Conners.
At No. 776, Yang became the lowest-ranked player in the world amateur standings to win the country's biggest title for non-professional golfers. Along the way, he beat five players inside the top 100, including the 44th-ranked Conners.
The 20-year-old Yang, a San Diego State player, never trailed in the 36-hole final at Atlanta Athletic Club, pushing his lead to 2 up with four to play by rolling in an 18-foot birdie putt at No. 14. He closed out the match with a tap-in par at No. 17, the 35th hole.
The South Korean was 1 up after the morning round. Afternoon play was halted by a rain delay of 1 hour, 37 minutes.
Marc Warren earns third European Tour win
Scotland's Marc Warren held off Bradley Dredge to win Made in Denmark by two shots, shooting a 3-under 68 in the last round to secure his third European Tour title.
Warren and Dredge were tied atop the leaderboard overnight but Warren surged ahead of the Welshman with three birdies on his first eight holes to open up a four-shot lead. Warren made two more birdies coming home and could afford his second bogey on the day on the 18th hole for a 9-under 275 total.
It was Warren's first title since winning the 2007 Johnnie Walker Championship, after several recent near misses.
Dredge finished with a 70 after mixing six birdies with five bogeys, ending with a 7-under 277 total.
Laurie Rinker wins The Legends Championship
Laurie Rinker won The Legends Championship when heavy rain forced tournament officials to cancel the final round at French Lick Resort in French Lick, Ind.
The 51-year-old Rinker, a two-time winner on the LPGA Tour, had rounds of 71 and 66 for a 7-under 137 total on the Pete Dye Course. She earned $60,000 in The Legends Tour event.
Sherri Steinhauer was a stroke back after shooting a course-record 63 on Saturday.
Rosie Jones was third at 4 under.