"Just one of those God-awful nightmare scenarios that happened today," Duval said. "And I happened to be on the end of it."
Duval, who plays sparingly now because of work with Golf Channel, liked his form when he arrived and even opened with two birdies to get his name on the leaderboard during a morning start. That ended with a quadruple-bogey 8 on the downwind fifth hole because of two lost balls.
And that wasn't the worst of it. Not even close. The par-5 seventh hole, one of the two additions to Royal Portrush, weaves between dunes with a stiff wind off the North Atlantic into the players. Duval sent his shot into high grass where it was likely to be lost, so he hit a provisional.
So far, not bad.
"The marshal had another ball," Duval said. "I asked if it was a 2 - Titleist 2. And then I looked at it and saw 2 and then played almost the entirety of the hole, and it turns out with the wrong ball."
The mistake was discovered by Zach Johnson's caddie. However many shots Duval hit with the wrong ball didn't count toward his score, but he received a two-shot penalty for playing the wrong ball - this after already getting two shots for losing the original tee shot. And the provisional ball was deemed lost, so that was another two shots.
The only way to account for playing the wrong ball was to return to the tee to start over.
From there, he was hitting his seventh shot and hit that one into the hay. He found it - buried, of course - and could only chop out. Some five shots later, he was back where he was when he first realized he was using the wrong ball - short of the green - and finished off his 14.
The first score posted was a 15. Then, it was quickly revised to a 13. After a few hours, the R&A realized he was given only a one-shot penalty for hitting the wrong ball, so it was adjusted to a 14.
Either way, it wasn't a lot of fun.
"Very unique, awful situation," Duval said.
But he played on, making a triple bogey on the 17th hole. The 91 is the highest score of his career, which includes a 59 in the final round of the Bob Hope Classic in 1999 when he was on his way to No. 1 in the world. His previous high round on the PGA Tour was an 83, most recently in 2003 at the Greater Hartford Open.
Duval won the British Open at Royal Lytham & St. Annes in 2001 and is exempt through age 60. He has played five times this year, including a Korn Ferry Tour event near his home in Colorado last week.
He never considered withdrawing to spare the embarrassment of such a big number. It matched the second-highest score in British Open history, behind the 15 that Herman Tissie made on the short "Postage Stamp" eighth hole at Royal Troon in 1950.
"You have an obligation as a professional athlete. If you play, you post your score," Duval said. "Am I happy about that? Is there some ... embarrassment to it? I don't know. But I teed off in the Open and I shot 90 today. So put it on the board."
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