Larry Nelson and Jay Sigel are tied for fourth place a stroke behind the leaders at 5-under-par 67.
Jack Nicklaus and Lee Trevino headline a group in sixth place at 4-under-par 68. Both players, who are 63 years old, were invited as sponsor's exemptions.
Tom Kite, the 2002 champion, opened with a 3-under 69 and his first-round playing partner, Arnold Palmer turned in an impressive feat of his own. Palmer matched his age Friday with a 1-over 73. Last year, Palmer matched his age at the Napa Valley Championship in October.
Irwin flew out of the gate Friday with three birdies in his first four holes. He two-putted from 20 feet to secure birdie at the par-5 seventh to make the turn at 4-under 32.
The 2002 Champions Tour money leader and Player of the Year took advantage of his next par-5, the 566-yard 10th. He two-putted there for birdie and also birdied the final par-5, the 14th. Irwin could not reach the green in two at 14, but wedged his third to nine feet to set up his final birdie of the round.
'I played okay today,' said Irwin, who won this event in 1997, 'I hit some loose irons coming in. I'm not quite geared into how far I'm hitting the ball with the new equipment. Everything in the bag is new except the putter.'
Veriato, who grew up in nearby Hilo, three-putted from 10 feet for a bogey at the third but that was his lone mistake of the round. He chipped in for eagle at his next hole, the fourth, and added two birdies on his front nine for a 3-under 33.
He blew an eagle chance at the 10th, but collected a birdie at No. 11 when he drained a 10-footer. Veriato ran home a six-foot birdie putt at the 14th and closed with a 20-foot breaker at the last to polish off his round of 66.
'This is a great spot to be in,' said Veriato. 'This is a big week for me. It's home. If I can shoot for pins, I will.'
Veriato is here on a sponsor's exemption this week as he lost his playing card in 2002. He finished 61st on the money list and lost a spot in Q-School.
'I'll be a qualifier from this point on,' said Veriato, who won the 2001 Novell Utah Showdown. 'I'll try to Monday qualify every other week. I'll be happy if I can get in 12-13 events.'
Quigley, who started his 202nd consecutive event for which he was eligible, holed a 15-foot eagle putt at four and tallied back-to-back birdies at seven and eight.
Quigley carded two birdies in his first five holes on the second nine, but missed a three-footer to save par at the 15th. He rebounded from the miscue at 15 with a 10-foot birdie putt at the last to grab his piece of first place.
'I played great and I have been all winter,' said Quigley. 'I've always played well here. This is my favorite place to play on tour.'