Jordan Spieth of the United States plays a shot from...

Jordan Spieth of the United States plays a shot from a bunker on the sixth hole during the third round of the 2018 PGA Championship at Bellerive Country Club on Saturday in St Louis, Missouri. Credit: Getty Images/Richard Heathcote

ST. LOUIS — He called it a perfect storm, brought about by a less than perfect golf shot.

Jordan Spieth worked a miracle to win last year’s British Open, salvaging a bogey from a driving range. Saturday in the third round of the PGA Championship, there was nothing miraculous, only disastrous.

This has been a difficult summer for the 25-year-old Spieth, who in 2015 became the first person since Jack Nicklaus in 1972 to win the Masters and U.S. Open in the same season.

Spieth reworked his swing — “I spent two months nailing the wrong thing,” he confessed — and has struggled to, as he said, “climb back out of it.”

The ascent seemed to be working. Spieth had birdies on five, seven, eight and nine in the third round to get to a cumulative 7 under par. But he made a bad swing at 12, the 452-yard par-4 at Bellerive Country Club, and followed that up with some bad judgment.

He attempted to get his second shot through an opening in a tree. Clunk. The ball hit the trunk and ricocheted out of bounds.

Spieth wound up with a triple-bogey 7, not only dropping off the leader board — he’s tied for 24th after 54 holes — but bringing memories of another awful 12th hole, 2016 at Augusta in the Masters, when he hit two balls into the water for another 7, a quadruple bogey.

That Spieth managed to shoot a 1-under 69 Saturday for a three-round total of 206 might be as discouraging as it is encouraging. He believes there has been progress, yet there also was the critical mistake.

The PGA is the only one of the four majors Spieth hasn’t won, and that probably won’t change until May when the 2019 PGA is held at Bethpage Black, although Spieth is thinking more positively than others.

“I know I can shoot around 7 or 8 under,”he said of Sunday’s final round, where he will start eight shots back of leader Brooks Koepka.

Spieth had a great last round in this year’s Masters, shooting an 8-under 64 to finish third. But after making swing changes, he missed the cut in the U.S Open at Shinnecock Hills and tied for ninth in his defense of the British Open title.

“I wasn’t working on the right things,” Spieth explained, which sounds odd for someone who was named PGA Tour Player of the Year for 2015.

“So from there, it’s been phenomenal what I’ve been able to do in my mind,” he said. “I’ve made what I thought would take weeks, kind of a turnaround to be able to trust and hit some really quality shots and work my way up to a major championship in a span of hours.”

But the errors on the 12th are an indication that he still has work to do.

“I squatted a little on the tee,” Spieth said, “and playing a draw, I hit it off the toe. Then I thought I had a shot and didn’t quite pull it off.”

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