The 64-year-old Nicklaus shot a third-round 76 at Valhalla on Sunday. He backed out of the tournament after two bogeys on the front nine of his final round.
Nicklaus designed Valhalla, which opened in 1986. He was heading to another of his courses, Muirfield Village, to play in this week's Memorial, the tournament he organizes.
Nicklaus, the winner of 73 PGA Tour events and 18 major titles, hinted he could be cutting back his schedule.
'I don't have anything else on my schedule the rest of the year,' he said. 'I'm going to play father-son stuff and Skins games and that kind of stuff, you know, if I'm invited. I might play an odd tournament here and there, but only if the mood strikes me and I want to go play.'
Nicklaus and Ben Crenshaw were among a growing list of withdrawals from the Senior PGA Championship.
The tournament has been delayed four times in four days by storms and organizers were expecting more players to back out Monday.
Kerry Haigh, the PGA's managing director of tournaments, said he understood the players' frustration.
'None of us like stopping and starting and having an inch of rain every night and having wet feet and wet pants,' Haigh said. 'But we're keeping a positive attitude on it.'
Haigh was hoping that a decent crowd would come out to see the tournament's conclusion Monday.
All patrons who had Sunday tickets would be admitted Monday, Haigh said. Tickets for Monday's final round were $20.
'We have a great leaderboard, we have a great championship and if Mother Nature does give us a break, we're looking forward to a really exciting day,' Haigh said.
John Harris had the shot of the day before play was suspended Sunday, nearly holing his approach to the par-5 18th.
Harris hit a 4-iron from 203 yards that lipped the cup and stopped six inches away. He tapped in for a 3, just the fourth eagle on 18 through three rounds.
Harris was at 5 under, two shots behind leader Hale Irwin.
Hale Irwin was going for several career milestones this week at Valhalla.
A win Monday would give Irwin his fourth Senior PGA title. Only Jack Nicklaus, a four-time winner of the Tradition, has more wins at one seniors major.
Irwin, who will turn 59 on June 3, is also trying to become the oldest player to win a seniors major since Pete Cooper won the 1976 Senior PGA at age 61.
Irwin won the Liberty Mutual Legends of Golf earlier this year and a victory at Valhalla would give him multiple wins for a record 10th straight year.
Irwin was at 7 under and led Dave Barr and Jay Haas by one shot when final-round play was suspended Sunday night. The tournament was due to resume early Monday.
Irwin doesn't blow leads often. He's won 26 of 36 seniors events he's led heading into the final round.
Copyright 2003 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.