The ecstasy belonged to Ian Poulter, whose seven-under-par 65 set a target matched late in the day by Scot Martin Laird.
The agony was Paul Casey's. Out for more than two months after dislocating his shoulder snowboarding on Christmas Eve, he was struggling with it again and after taking 42 to the turn withdrew on the next.
It not only ended his hopes of a first prize of well over £1 million, but was a further blow to his chances of playing in the Ryder Cup this September.
He was not alone in that. Simon Dyson pulled out with back trouble after a 76.
Casey said: "My shoulder felt tired and tender when I made my way to the first tee.
"I decided to give it a go as I thought I could play through it, but during the round it flared up, which is when I decided to withdraw.
"I am very disappointed. My game has been coming around and I felt confident, but my body told me otherwise.
"My recent schedule has been extremely busy and the lack of rest has taken its toll. It's a long season and my health is the number one priority."
Poulter, runner-up to Swede Henrik Stenson three years ago, knocked two strokes off his previous best score on the course and described it as one of the top 10 rounds of his career.
He and Laird, who kept a bogey off his card, were a stroke ahead of little-known American Blake Adams, but Tiger Woods was nine strokes back and in danger of a second successive missed cut - something he has never suffered before.
Woods was just outside the top 100 as the day's play drew towards it close and said: "Any kind of momentum that I would build I would shoot myself in the foot on the very next hole.
"For some reason it's just been one of those weird deals. Out here (on tour) you have to take care of the par fives and I haven't done a very good job of it lately.
"It was frustrating in the sense that my good shots ended up in bad spots and obviously my bad shots ended up in worse spots.
"In the last few months I've put together some good rounds and won a couple tournaments, so it's there - I just need to continue doing it."
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As for Rory McIlroy, Luke Donald and Lee Westwood - battling for world number one - it was a day of mixed fortunes.
McIlroy, who went top again by being in a play-off at Quail Hollow last week, was going best until he went in the water on the short 17th.
Angel Cabrera had put three balls in there earlier on and ran up a nine. McIlroy took five and finished with a 72 like Donald, who birdied the same hole, while Westwood matched Phil Mickelson's 71 with a round that included seven birdies, four bogeys and a double bogey on the seventh.
Poulter said: "I played lovely. I hit it really, really solid."
He also had nine one-putts in a row from the ninth - that helps.
"You have to hit the right shot at the right time - it's a very, very difficult course and tests you to the highest."
First prize is well over £1 million and, on the car of his dreams - a Ferrari Enzo - Poulter said: "I've been looking for one of them for a while.
"It will be a nice addition to the stable. I haven't got room, but I'll find room - trust me. A couple of buggies will go, I think.
"I like that it's a proper challenge. You have to hit the right shot at the right time - it tests you to the highest.
His score was two strokes better than his previous best on the lay-out, but Laird knocked five shots off anything he had done before at the PGA Tour headquarters.
That was down to his putting, the United States-based Glaswegian said.
"I finally made some. I've always struggled here before and when it's hard to get close to the pins you have to hole some putts."
Victory for him would catapult him into the Ryder Cup reckoning after he gave all his rivals a four-month start by not being a member of the European Tour last year.
Poulter put some of his success down to a clear mind at long last.
A two-year saga over the building of a new home in Orlando is about to end. He moves in this weekend.
"I do fill my brain full of lots of funny things at times," he said. "It's nice when that's empty and I can do what it is I love to do - go out there and play golf.
"Last week I was filling boxes and opening boxes - I barely hit a shot.
"It's no surprise to me to be fresh in the mind this week. I'm relaxed and the family are happy - all of the hassle and stress is over."
Next best of the European contingent was Londoner Brian Davis - another who bases himself in America - with a 68, one better than Padraig Harrington.
Lee Westwood won the battle of the three Europeans at the top of the world rankings, but only by one after a 71 and only thanks to McIlroy going in the water on the short 17th for a double-bogey five.
That was still four strokes better than Angel Cabrera there, though. That sextuple bogey - he put three balls in the lake - took him from level par to six over and he will not be back for the second round.