He earned $315,000 for his sixth career victory on the 50-and-over tour, and improved two spots to No. 7 in the Charles Schwab Cup standings in the tour's regular-season finale.
The victory "gives me a huge amount of confidence going into the playoffs, and I look forward to the next few weeks with added incentive now," Montgomerie said.
The 54-year-old Scot finished at 16-under 200. He won the tour's first-ever event in Japan — the Japan Airlines Championship — last month. The Hall of Famer won 31 times on the European Tour and topped the tour's money list a record eight times — seven in a row from 1993-99 and the last in 2005.
Vijah Singh and Doug Garwood each shot 66 and tied for second at 13-under 203. Corey Pavin was one stroke behind them after his 67.
"I was just trying to make birdies," Pavin said. "That's all I could do out there. I just hit a couple bad putts. But I hit a lot of good shots. I can't really think of a bad shot I hit really. So pleased with my ball striking."
Bernhard Langer shot 69 to finish tied for 11th and push his season earnings over $3 million. The 60-year-old German star leads the Schwab Cup standings by nearly $600,000 over second-place Scott McCarron.
Montgomerie had two bogeys during his three rounds in suburban Raleigh — only one on his final 51 holes.
"The standard of golf here is extraordinarily high," Montgomerie said. "Every time you make a birdie, you feel you have to make an eagle because someone else has made a birdie."
He began the final round sharing the lead with Phillip Price and Jerry Kelly. He had three birdies on the front nine before pulling away with five birdies on the back nine — including on the 14th, 15th and 17th holes — before closing with a par on the par-4 18th.
Montgomerie is trying to stay in peak form for the Schwab Cup playoffs — which begin next week in Richmond, Virginia, for the top 72 players — after he started the season slowly because of injuries. He was sidelined for 2½ months in the spring by torn ligaments in his left ankle.
Montgomerie said he plans to arrive in Richmond on Tuesday "and grinding it out and see what we can do there as well.
"Have to keep going," he said.
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