Scott Stallings is latest to learn how quickly fortunes can turn ugly in golf

Golf celebrates its winners and tortures its losers. It isn’t a game, it’s a giant thumbscrew.

At first glance, Sunday presented the opposite. Everything was idyllic in the California desert, where they play the Humana Challenge (formerly the Bob Hope) every year at this time.

It isn’t always like it was on this tournament closing day at the Palmer Private Course in La Quinta, where the temperatures drifted into the high 70s, the skies were bluer than a decked-out Bruin on the 50-yard line, and the swaying palm trees never swayed. Never even twitched all day.

A year ago, the wind blew so hard on the third day of the tournament that it deposited the scoreboard into the pond alongside No. 18 and several fans on their backsides. Six years ago, when this event was played at the Classic Club, in a wind tunnel on the north side of the 10 Freeway, it blew so hard on the final day that spectators were getting as sandblasted as golf balls in the bunkers.

They eventually brought the tournament back to the shelter of the Santa Rosa Mountains, and seldom has that decision looked any better than Sunday. It felt more like a picnic than a competition. The grass wasn’t mowed, it was manicured. The sand traps weren’t raked, they were artistically smoothed.

The competition felt like an unobtrusive sideshow. Scott Stallings entered the day with a five-shot lead and birdied three of the first four holes. This looked like one walk in the park that couldn’t be spoiled. Golfers quietly paraded past. Spectators — average age probably 55 if you factored in the dozens of babies in strollers — sipped and munched and watched. Suntans for 2013 took root.

The talk was that five shots would be almost impossible to overtake, especially with a golf course such as this —challenging for the weekend golfer but duck soup for the pros. From the start, there had been almost nothing but 60s — low 60s for that matter — on the leaderboard. Shoot 70 in this event and get needled in the locker room. Were Stallings to shoot 68, the other guys could forget about it.

The expectation for low scoring didn’t change. When it ended, the scores for the day for the top six finishers read, as follows: 63, 62, 64, 62, 70, 64 and 65.

Ah, but guess who shot the 70? Yes, one sad, frustrated guy named Stallings.

“You can’t make mistakes like that,” Stallings said afterward.

He had let the five-shot margin slip away, as Brian Gay, Charles Howell III and Kevin Chappell went low and took runs at the lead. A 24-year-old named James Hahn eagled the 18th hole to get into the mix. A Swede with little PGA Tour name recognition, David Lingmerth, 25, matched Hahn’s 62. Even the venerable veteran Stewart Cink, turning 40 in May and the only one on the leaderboard with even a sniff of a major title (his British Open in 2009), cranked away for a while with illusions of grandeur. Had he birdied the par-three 17th hole and eagled the par-five 18th, he would have won outright. Instead, he finished five-five. Thumbscrews.

Stallings, a 27-year-old with two tour victories and his first child within weeks of being born, stood on the 18th fairway with a six-iron in his hand, as well as control of the tournament. If he hit it decently onto the green and two-putted for a birdie, he would win. If he needed three to get it there and two putts, he was into a playoff with the already finished Gay, Lingmerth and Howell III.

Stallings hit the six-iron off the rocks and into the water. He got a drop and could have chipped in for the birdie and the win, but said later that goose poop got on his ball when he dropped and altered his shot. His chip rolled well past, he made a six and wasn’t even in the playoff. Goose-poop thumbscrews.

On the first playoff hole, back at No. 18, Lingmerth got a bad lie for his second shot and yanked it badly left into the water. “I thought [Stallings] was going to run away with it,” Lingmerth said.

He was done and Gay and Howell III went on to the second playoff hole, No. 10.

Gay drove it down the middle, Howell III into the rough and then the back bunker. It was over. Gay’s birdie putt made it official. He was the winner of the Humana. Howell, who came on the scene as a possible future superstar in 2000, hasn’t won since 2007 at Riviera.

“I think this is my 15th or 16th second-place finish,” said Howell, who actually has 14 such finishes.

Double thumbscrews.

Drama and excitement had ruffled a day of calm and postcard beauty. First came the tease, then the torture.

Even Phil Mickelson stirred the glassy waters. Not with his golf, where he shot 72-67-66-66 — 271 and tied for 37th, but with some perceived political activism. He made some thinly veiled remarks about the recent high tax rates about to be imposed on people in his income bracket, and about how it could force him to depart residence of his beloved San Diego for a state without income tax.

“I will be making some drastic changes,” he said, adding that he will have more details at next week’s Farmers Insurance Tournament at La Jolla.

So, Phil will make us wait a few days for more. Typical golf. Torture.

bill.dwyre@latimes.com