Quigley was joined at the top of the leaderboard on the South Course at The Reserve Vineyards & Golf Club by John Harris, Loren Roberts and D.A. Weibring.
Allen Doyle, who shared second place here last year, carded a 4-under-par 68. He was tied one shot behind the leaders with Walter Hall, Mark Johnson, Mark McCumber and R.W. Eaks.
Weibring got off to a hot start with birdies on the first and third. After three straight pars, the 52-year-old moved to 3 under with a birdie on the par-3 seventh.
The three-time winner on the Champions Tour dropped a shot on the ninth and then ran off three consecutive pars from the 10th. Weibring birdied each of his last three holes to share the lead.
Quigley, whose ironman streak ended when he missed the Senior British Open, stumbled to a bogey on the par-3 second. He got that stroke back with a birdie on the par-5 sixth.
The 10-time winner on the Champions Tour moved into red figures with a birdie on the 11th.
Quigley, who played with Weibring, came back two holes later with his third birdie of the round. He birdied the par-5 15th to move to minus-3. The 58-year-old eagled the par-5 closing hole from 45 feet out to grab a share of the lead.
'Seemed like 25 feet. I must be putting well,' joked Quigley about the putt's length. 'When you see a guy playing well, it tends to get you stirred up to play well. We didn't spend much of the day looking for balls or seeing clubs being slammed to the ground.'
Harris, the least known of the four leaders, got off to a hot start with birdies on one and three. He moved to minus-3 with a birdie on the fifth.
The 53-year-old parred his next eight holes before sinking a birdie try on the par-3 14th. He came right back to birdie 15 before parring his last three holes.
'I need to take advantage of it and play all the way through,' said Harris, who tied for third in Seattle last week. 'But it's a nice start
Roberts, playing in just his third Champions Tour event after turning 50 in late June, opened with a birdie on No. 1. He slipped to a bogey at the next.
The eight-time winner on the PGA Tour came right back with a birdie at the third. Roberts made it two straight with a birdie on four. He moved to minus-3 with a birdie at the fifth.
Roberts then birdied the seventh. After seven straight pars, he birdied 15 and 16 to get to minus-6. However, he dropped a shot at the par-4 17th to drop back into a share of the lead.
Gil Morgan, a two-time winner of this event, opened with a 3-under 69. He was tied for 10th by Dave Barr, Tom Jenkins and Bruce Summerhays.
Graham Marsh, the 1999 Tradition winner, is one stroke further back at minus-2 and stands alongside 1999 runner-up Larry Nelson, Don Pooley, John Jacobs, Dave Stockton and 2001 champion Doug Tewell.
Defending champion Craig Stadler is tied for 34th after opening with an even-par round of 72