AP Sports Writer
SAN FRANCISCO (AP) - Louis Oosthuizen's drive drifted deep into the right rough. He laid up short of the green and stood in awe while measuring up his third shot.
Only 240 yards remained.
"If anybody is on the green in two this week, that's something special," Oosthuizen said of the longest hole in U.S. Open history, the remodeled par-5, 670-yard 16th at The Olympic Club.
If length weren't enough, the sharp dogleg left feels like a constant U-turn and the fairway narrows right at 300 yards.
The flag is often blind until the third shot, and ones that miss long or left will bounce even farther away because of the grass mowed razor-thin beyond the tiny green.
"The reason we did that is we really felt that would make it a true three-shotter," said USGA executive director Mike Davis, who oversees the course layout. "The wonderful thing about that hole is that from the back, if you miss any one of your shots, it's awful hard to catch up."
Players already are finding out firsthand in practice rounds.
Oosthuizen, the 2010 British Open champion, could never remember pulling out a 5 wood for his third shot before, hacking out of so much rough _ "the thickest on the entire course," he said _ on the previous swing he had no choice.
Staring up at the elevated green, he couldn't imagine even the field's longest hitters _ Dustin Johnson and Bubba Watson among them _ going for the flag in two, even under the best of circumstances.
"It's too risky," Oosthuizen said. "The neck there on that fairway or the green is what, 6-7 yards wide? You're going to overrun it."
Michael Thompson, the 2007 U.S. Amateur runner-up at Olympic Club, drove into the graded rough Monday. He laid up to 180 yards in front of the green and still had to hit a 5 iron.
"When do we ever hit a 5 iron on our third shot on a par 5, ever?" Thompson said, laughing. "I think what makes it difficult is it's guarded in front with a bunker. For a long shot coming in, it'd be hard to hold the green."
Lucas Glover, the 2009 U.S. Open champion at Bethpage Black, played the 16th in his first practice round about the best anyone could hope to this week. He drove into the fairway, hammered a 3 wood short, floated the ball onto the green with a sand wedge and two putted for par.
The walk alone still wore him out.
"That hole is all you want," Glover said. "I don't know that anybody, without a serious wind at their back, could get there in two. Getting there? Maybe. Getting the ball to hold? There's no chance. It's a three-shot hole for sure."
The unleveled Lake Course is short by most U.S. Open standards.
The course plays at a par-70, 7,170 yards _ 373 yards longer than the last time it hosted the national championship in 1998 _ with the biggest gains coming from the 16th hole. The tee is so far back from the 15th green that it often throws off players, who have to walk about 100 feet backward for the next hole.
K.J. Choi decided to take a shortcut in his opening practice round through the fans instead of walking through the roped-off path that makes it even longer.
"Taking the short route?" one spectator asked.
"No short route here," Choi jokingly responded.
The USGA's Davis expects to use the new tee for two of the four rounds, including Sunday's final. He also plans to put tees out at 570 and 630 yards, and the shortest of those could make "golf's toughest test" even trickier.
On that day, players with long _ and straight _ drives could be forced into an interesting dynamic: going for the green in two or laying up with the 522-yard 17th _ playing at par 5 for the first time _ setting up as the next birdie opportunity.
"Now with back-to-back par 5s," Davis said, "I think you will see the U.S. Open won or lost on those two holes."
The upward trend also has some players wondering where the limit lands.
The previous longest hole in U.S. Open history was the 667-yard 12th hole at Oakmont Country Club in 2007. No. 5 at the 2007 PGA Championship at Southern Hills played at 653 yards, and the 17th at the 2005 PGA Championship at Baltusrol extended to 650 yards from the back tees.
Davis has insisted the 16th at Olympic is not a gimmick or a way to level the playing field for the shorter hitters. Instead, it's simply meant to be a true three swings to the green, where shaping shots and placement are paramount.
Even still, that might not be enough to stop the most daring drivers.
"One thing I've learned playing out here," qualifier Patrick Cantlay said, "is somebody's always trying to reach it."
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