Tiger Woods and last week's U.S. Bank Championship in Milwaukee winner Carlos Franco carded matching rounds of 6-under 66 and shared third place at 21-under-par 267.
'It's great that I played that way, but it's frustrating I didn't win,' said Woods, who has only one win this season, the World Golf Championships - Match Play Championship. 'Things are starting to come together.'
Daly trailed Singh by two strokes at the start of the final round, but quickly erased the deficit. Daly holed a 9-iron from 144 yards for an eagle at the second and suddenly the margin was gone.
Daly was not finished as he ran home a 15-foot birdie putt at the third. He birdied the fourth also and found himself in the lead by one over Singh.
The duo both birdied the seventh hole and it wasn't until the 12th where Singh drew even. He drained a 12-foot birdie putt to match Daly atop the leaderboard at 22 under par.
The tie was short-lived as Singh sank a 12-foot birdie putt at No. 14 to go up by one. Neither player played terribly well off the tee, but each made par saves until the 16th.
Daly drove into the left rough at the par-5 hole and laid up short of the green. Singh roped a 3-wood on to the back fringe from 281 yards, but Daly pitched his third to a foot. Singh lagged to 4 feet and made the birdie putt. Daly tapped in his putt to remain one back.
Singh looked to be in trouble at the 17th when his 6-iron landed in the back bunker. Facing a difficult, downhill blast, Singh played a soft shot to 5 feet. Daly two-putted for par and Singh converted the par putt to make 18 the decisive hole.
Singh drove right into the trees at Warwick Hills' closing hole and Daly followed him. Singh chipped out from under a tree, but remained in the rough. His third stopped 5 feet from the hole.
Daly also found himself under a tree, but he punched down the fairway. His third landed 4 feet from the hole, but if Singh could convert his par putt, Daly would be second.
Singh pulled his putt left and opened the door for Daly, who won this year's Buick Invitational. Daly missed his par putt to match Singh's bogey and lose by one.
'I think we both got horrible breaks,' said Daly, who shot a 6-under-par 66 on Sunday. 'I know I did on 18. I really thought I hit a better drive than that. I got off to a helluva start and put some pressure on Vijay. It was a lot of fun today.'
Singh, who won this tournament in 1997, picked up his fourth win of the 2004 season. He won at Pebble Beach, Houston and New Orleans and with the $810,000 first-place check, Singh moved past Masters champion Phil Mickelson into first on the PGA Tour's money list.
'I was pretty nervous down the stretch,' said Singh, who is the third-ranked player in the world. 'I'm really proud of this. John Daly played really well today. On the fifth hole, I said to him, 'Okay, I've had enough.''
Now Singh sets his sights on the PGA Championship, a tournament he won in 1998, in two weeks.
'The putter's really working for me,' said Singh, who abandoned the belly putter after two and a half years this week. 'I hope I putt like I did today in two weeks time and everything will be cool.'
Woods tried to make a move later in his round. He ran home a 25-foot birdie putt at the 10th, then birdied both back-nine par-5s, 13 and 16. Woods hit his tee ball to 3 feet to set up birdie at the 17th, but could never threaten Singh and Daly.
'I felt good all week,' said Woods. 'I'm very pleased with the things I did this week.'
Stewart Cink picked up some Ryder Cup points on Sunday. He carded a final-round 66 and took fifth at minus-18.
Jim Furyk, the 2003 winner, shot a 4-under 68 and tied for sixth with Jeff Sluman, who posted a 66 in the final round. The pair came in at 17-under-par 271.
Jerry Kelly (66) and Daniel Chopra (70) tied for eighth at 16-under-par 272. Scott Verplank and Mark O'Meara both fired rounds of 66 and shared 10th at minus-15.