Haas closed with a 2-under 69 to finish at 12-under-par 201. The win was his third of the season and ninth of his Champions Tour career.
He matched Hale Irwin's hot start to a Champions Tour career. Irwin, and now Haas, both picked up nine wins in their first 49 tour starts.
'It's a thrill holding off some great players,' said Haas, who earned $240,000 for the win. 'Brad Bryant and R.W. Eaks came on there and David Edwards made a nice couple of birdies coming in. It was a long day, but it never seemed like the 18th hole was going to get here.'
Eaks fired a 7-under 64 in the final round to end in a share of second place at 9-under-par 204. He was joined there by Bryant (67). Jay Sigel joined Edwards and Mark James in fourth place at minus-8.
Haas, the reigning Champions Tour Player of the Year, got off to a solid start to put things out of reach. He dropped in a 6-foot birdie putt at the first.
The 53-year-old drained a 15-footer for birdie at the fourth to move six clear of the field at 12 under. Two holes later, Haas converted a 3-footer for birdie.
From there, Haas admittedly played against the scoreboard. He parred his next eight holes at Glen Oaks Country Club, but still comfortably led by five strokes.
Haas came up short and right of the 17th green. He pitched to 12 feet, but two-putted for bogey. At the last, Haas drove into a fairway bunker and pitched down the fairway.
He knocked his third to 33 feet, then two-putted for another bogey to drop his winning margin to three strokes.
'I was definitely playing the scoreboard there coming in,' Haas said. 'I got a little sloppy the last couple of holes, but I knew I had a nice cushion coming in. I was playing for bogey those last couple of holes.'
Eaks flew up the leaderboard with four birdies over the first six holes. He posted three birdies the rest of the way to cap a bogey-free round of 64. It was a strong round for Eaks, who has been battling a bad back recently.
'I was in the fitness trailer before the round and they worked on me for about an hour,' Eaks stated. 'I think I learned something. I need to get a massage out here every week. I've been having problems for about 12 weeks, but I think those guys showed me the light.'
Bryant, who defeated Eaks in a playoff at the Regions Charity Classic, stumbled out of the gate with bogeys at two and three. Bryant rebounded with three birdies over the next five holes to get to 6 under.
After six straight pars around the turn, Bryant birdied three of the last four holes to share second place.
Denis Watson, who won the Senior PGA Championship last month, played in the final threesome, but struggled to an even-par 71 in the final round. He shared seventh place with Morris Hatalsky and Irwin at 6-under-par 207.
Andy Bean, Chip Beck, Dave Stockton, Danny Edwards, Vicente Fernandez and Bruce Summerhays were two strokes further back at minus-4.