And for the longest time, it looked as though it might be costly.
Guan, playing with Matteo Manassero and Ben Crenshaw, was informed his group was out of position as it left the 10th green. They were on the clock on the 12th hole, meaning players would be timed to make sure they hit their shots within the 40-second limit. The teen got his first bad time with his second shot on the 13th hole, and it was clear he was in trouble after his shot into the 17th when John Paramor, chief referee in Europe, walked out to speak to him.
"You give him the news, the best you can," Paramor said.
Fred Ridley, the head of competition at the Masters, did not say how long Guan took to hit his second shot on the 17th, only that it was a "considerable margin" over his time. Guan still managed to make par on the 17th, and if he was shaken by the news so late in the round, it didn't show. He made one last par and was at 4-over 148.
His game is well beyond his years, and so was his attitude over the first slow-play penalty in a major since Gregory Bourdy in the 2010 PGA Championship.
"I respect the decision they make," said Guan, who spent nearly 90 minutes talking with officials after the round. "They should do it because it's fair to everybody."
The penalty looked ominous because Dustin Johnson was running off birdies every way imaginable, the only player to reach 7-under par in nasty conditions. His round imploded, however, when he played the final five holes in 6-over par. That included a double bogey on the 15th when he hit his third shot into the water. He had a 76 and plunged down the leaderboard, though he was still only five shots behind.
Furyk also hit into the water on the 15th with a wedge he chunked so badly that it didn't make it halfway across the pond. Scott made his third straight bogey at No. 5, but that was the last mistake he made. He answered with three birdies the rest of the way.
Day's 68 was the lowest score of the round, with conditions so tricky that only five players broke 70.
"It just feels like every shot is the biggest shot you've ever hit in your life out there," Day said. "It's really, really difficult. I'm just glad to be in the clubhouse right now."
One player who didn't recover was Sergio Garcia, who opened with a 66. One day after six birdies and no bogeys, he had four bogeys and no birdies. One day after he saw so many shots go where he was aiming, he couldn't cope with the wind.
"I hit the ball better today and was I was 10 shots worse," Garcia said after a 76 that put him in the group at 2-under with McIlroy, former Masters champion Charl Schwartzel and 55-year-old Bernhard Langer. "But even with everything that happened today, we still are in a decent position to hopefully do something on the weekend."
That weekend will include defending champion Bubba Watson, who will play with a marker in the first group Saturday morning, and Phil Mickelson, who shot 40 on the back nine and had a 76 that left him nine shots out of the lead.
And it will include an eighth-grader who is assured of winning the sterling silver cup as the low amateur. He was the only amateur to make the cut, penalty shot and all.
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