''David played a great round, and I knew someone was going to play well,'' Cochran said. ''I was hoping to hang around there and kind of catch fire. And it took every hole to do that.
''We knew we needed to make birdies, especially after the bogey on 13.''
The 54-year-old Cochran, also the 2010 winner at Prestonwood Country Club, closed with a 5-under 67 to finish at 17-under 199. The left-hander won The Principal Charity Classic in June in Iowa. He has five Champions Tour victories after winning once on the PGA Tour.
Frost finished with a 66. He missed a short birdie putt on No. 17 and also settled for par on 18.
''It's such a hard tournament to win, especially from the lead because you know everyone is back there firing at the hole,'' Cochran said. ''The drive on the 18th hole was a big deal because you've made these birdies now, and you don't ever want to give a guy like David Frost another chance.
''He's a tremendous player, one of the best putters and short game guys I've ever seen. He is unbelievable.''
Kirk Triplett was third at 14 under after a 68.
Gary Hallberg (66) was fourth at 13 under, and Michael Allen (70) and Anders Forsbrand (69) followed at 11 under. With the top-10 finish, Forsbrand qualified for the Greater Hickory Classic next week at Rock Barn.
Bernhard Langer, the 2012 winner, tied for eighth at 9 under. Langer, two strokes behind Cochran entering the round, had a 73. Charles Schwab Cup points leader Kenny Perry shot a 72 to tie for 11th at 8 under.
With the victory, Cochran moved into sixth place in the Schwab Cup race.