There was a weather stoppage early in Saturday's third round that lasted almost two hours. More inclement weather in the area at 5:30 p.m. (ET) caused officials to stop play again.
Play was suspended for the day an hour later and the 33 players who did not complete their third round will return to Laurel Valley at 8:15 a.m. Sunday morning. The golfers will complete the round, have lunch, then come back out in the same groups from the third round.
Dave Barr, who nearly withdrew before the tournament because of a bad back, is one-under on his round and is alone in fourth at minus-4. Ray Floyd and reigning U.S. Senior Open champion Peter Jacobsen are both one-under on their rounds and are tied for fifth at 3 under par.
Quigley, the winner of the season-opening MasterCard Championship, bogeyed the second hole, but reclaimed the lost stroke with a four-foot birdie putt at the par-5 third.
The Champions Tour iron man with 273 consecutive starts for which he was eligible, Quigley chipped in from off the green for a birdie at the seventh to reach 4 under for the championship.
Quigley rolled in a 3-foot birdie putt at the 11th to match Pate and Reid for the lead.
'I'm really loose out there and there's no substitute for confidence,' said Quigley. 'I'm in a good mindset. Going out there and having fun is a key ingredient for me.'
Pate wasted little time in extending his one-shot, second-round lead. He sank a 7-foot birdie putt at the first hole, but the 1976 U.S. Open champion struggled the rest of the way.
He hit a terrible second shot at the par-5 sixth, a hole he birdied in both previous rounds. Pate left himself with 25 feet to save par, and his putt moved left at the last second.
Pate fell into a tie for the lead at the eighth when his tee ball at the par-3 hole missed the green. His second came up 12 feet short, and Pate missed the par putt.
'I started out really swinging well,' said Pate, who will be searching for his first victory since joining the Champions Tour last year. 'My putter is terrific, I just have to swing within myself.'
Reid birdied the first hole for the third time in as many rounds, when his 9-iron approach stopped 10 feet from the hole.
That was it for Reid's birdies on Saturday. He had a 6-foot look at birdie on the 10th hole, but his putt never fell. However, the 50-year-old now has a good chance at not only his first Champions Tour major, but his first win on the 50-and-over circuit.
'I had two good chances for birdie and made one out of the two. So I was in good rhythm today and very pleased with my play,' said Reid, who has not won since the 1988 NEC World Series of Golf. 'Hopefully I'll pick it up where we left off tomorrow.'
R.W. Eaks, who was alone in second place after the second round, is 3 over through 10 holes. He shares seventh place with Tom McKnight, who is 1 over through 11, at 2 under par.
Mark McNulty (3 over) and Hajime Meshiai (2 over) are knotted in ninth at minus-1.
Defending champion Hale Irwin is 6 over through 14 holes and is 6 over for the championship. He is part of a group tied for 42nd place, 11 shots behind the leaders.