Fresh off a win at the MasterCard Championship on the Big Island, Roberts shot a 6-under 66 on Friday in the first round of the Turtle Bay Championship to take a one-stroke lead over Bruce Summerhays.
Five-time defending champion Hale Irwin had trouble finding his groove and carded a 1-over 73 in the Champions Tour's first full-field event of the year. Irwin bogeyed No. 3 and parred the next 15 holes.
Irwin is seeking his sixth straight Turtle Bay title but it was Roberts who continued his strong play in Hawaii.
'I feel comfortable and I feel good with the way I'm swinging,' Roberts said. 'I'm not having to make a lot of swing thoughts. I'm basically getting up there, seeing the shot and ripping at it.'
He sank putt after putt, making the turn at 33 and recording seven birdies, including four in the last seven holes. The 66 was the lowest first-round score on the oceanside Palmer Course.
Roberts sank a 22-foot birdie on the 530-yard No. 3 to get his putter going. He took the lead on No. 18 by holing a 3-footer for birdie set up by a nice chip from the fringe.
'I hit the ball solid all day,' he said. 'You can't shoot under par when the winds are blowing like this without hitting the ball solidly. That's the whole key to playing in the wind.'
He missed just two greens in regulation.
Last week, Roberts had a 25-under 191 in ideal conditions at Hualalai course to shatter the Champions Tour record for relation to par in a 54-hole event. He also broke the tour record for birdies in a three-round tournament with 26.
'You can't predict how things go, but I did feel really ready to play this year,' said Roberts, who tied for 18th at the PGA Tour's Sony Open. 'My game was in order when I showed up.'
Roberts, an eight-time winner on the PGA Tour, joined the 50-and-over tour in July 2005 and finished 16th on the final money list in just six starts.
Don Pooley, who lost to Roberts by a stroke at Hualalai, was two strokes off the lead at 68.
The field of 78 was challenged by the breezy and damp conditions.
'It was really windy and blustery,' said Summerhays, who tied for second in 1997 and tied for third in 2003. 'As a matter of fact, on the last hole I almost got bamboozled out there.'
Summerhays, who turns 62 next month, got off to his best start at Turtle Bay. He birdied three of the par-3s, but none of the par-5s.
He had a chance to move to 6-under, but three-putted the final hole for par.
Summerhays played in front of more than 30 family members, down from 44 that watched him last week at the MasterCard Championship on the Big Island.
Japan's Kiyosi Murota making his Champions Tour debut on a sponsors exemption, was at 69 with former Hawaii resident Scott Simpson, Jim Thorpe and Mark Johnson.
'I got nervous on my first four or five holes, but then I decided to just enjoy myself and I played pretty good,' said Murota, who birdied three of his final four holes.
Simpson, a native of San Diego who lived in nearby Kailua for five years, began the day with an eagle on the par-4 first by holing his approach shot using a 6-iron from 167 yards.
He told playing partner Morris Hatalsky: 'There's two ways to look at it: It's a great way to start the year, but it can only go down hill.'
The group at 70 included Jerry Pate, Tom McKnight, Raymond Floyd, Ben Crenshaw, Lonnie Nielson, and Jay Haas.
Isao Aoki and Tom Watson were another stroke back.
Last year, Irwin won at Turtle Bay with a record 16-under 200 to become the first player to win a PGA Tour-sanctioned event five straight times.
Tom Purtzer withdrew with a sore back and was replaced by Jim Chancey. ... The Palmer Course, built on a marsh, was used by the Army as a landing strip for bombers and housing area during World War II. ... Roberts, Haas, Peter Jacobsen and Craig Stadler opened their season by playing in the Sony Open in Hawaii on the PGA Tour.