BETHESDA, Md. (AP) -- Roberto Castro missed the U.S. Open at Merion. It felt as if he was playing one Thursday in the AT&T National at Congressional.
The course that has hosted three U.S. Opens looked as though it could hold another in a moment's notice. Only a dozen players shot in the 60s, with Castro leading the way at a 5-under 66 that required some of his best golf. He made three straight birdies late in his round with a 20-foot putt, a perfect 3-wood into a par 5 and a chip-in.
"It's very similar in that there's not a lot of birdies out there," Castro said. "There's not many good breaks or bad breaks to be had out there. If you drive it in the rough, you drove it in the rough. If you hit it in the fairway, you can go from there."
The average score was just over 73, despite cloud cover for most of the day leading to soft conditions and only a light wind.
Billy Horschel, who tied for fourth in the real U.S. Open two weeks ago, began his day with a 50-foot birdie putt, added a pair of birdies over the next three holes and then hung on for a 68. That was the best score among the early starters. Bud Cauley and Graham DeLaet each had a 68 in the afternoon.
"It's like another U.S. Open," Horschel said. "Off the fairways, the rough is thick. Fortunately, the greens are soft so they're really receptive. It's still a tough golf course."
The eight players at 69 included Jim Furyk, 19-year-old Jordan Spieth and Brandt Snedeker, whose round included a birdie on the par-5 ninth hole in which he covered more than the 635 yards it was playing.
Snedeker snap-hooked his drive into the rough and was blocked by trees, leaving him no choice but to chip backward or play down the adjacent fourth hole. He hit hybrid down the fourth, and just his luck, wound up on the member's tee. From about 180 yards, he hammered a 6-iron through more trees, and the big roar told him he had reached the green. From there, he made a 55-foot birdie putt. Simple as that.
"Kind of stealing a couple there is what it feels like," he said.
Davis Love III had an 83 with a sore hip and then withdrew, not wanting to risk further injury. Rory Sabbatini withdrew with a sore back after he was 8 over in 12 holes. Charlie Beljan had an 84.
Lucas Glover, a former U.S. Open champion, called it "the most boring round of PGA Tour golf I've heard."
"I heard two cheers across the whole golf course all morning," Glover said after a hard-earned 71. "They definitely weren't for my group."
There were no tricks at Congressional, and there certainly was no faking it. Masters champion Adam Scott hurt himself with an ordinary day by his standards off the tee and wound up with a 73. Hunter Mahan hit only six fairways - he's one of the best drivers in golf - and shot a 75.
Officials cut the rough Wednesday, though its thickness presented the bigger problem than the height of the grass. It's tougher than Congressional was for the U.S. Open two years ago, when the course was relatively soft throughout the week. Rory McIlroy played better than anyone that week and won by eight shot at a record 16-under 268.
This was more of a grind.
Castro made only one bogey, and that was from the fairway. After a weak drive, he put his second shot on the 11th into the water, and saved bogey with a chip to tap-in range. He bounced back with consecutive birdies, and twice made solid par saves before his run of birdies on his back nine.
But it was a quiet day for the most part.
"Two U.S. Opens in three weeks," said George McNeill, who had a 71 while playing with Jonas Blixt and Ben Curtis. "And before that, we got to play the U.S. Open at Muirfield (Village), too. It was fairly quiet out there. You have a few cheers here and there. But we had the `hot dog' group. That's where the fans are looking at the pairing sheet and go, `Curtis, Blixt, McNeill. Let's go get a hot dog."'
It didn't help that Tiger Woods wasn't around, unable to play because of a sore left elbow that will keep him out of competition until the British Open next month.
Woods won last year at 8-under 276, one of the higher winning scores on tour in 2012.
"You don't usually see first-round scores on a PGA Tour event only be 3-under leading after the morning wave," Horschel said. "It shows you how tough this golf course is, shows you how long the rough is."
Horschel, though, said he likes it that way because it doesn't feel like a putting contest.
As for not having Woods around? Horschel doesn't look at the AT&T National any differently without him.
"Tiger is Tiger. He's just another guy," Horschel said. "He's just another player out there. For me, thinking about someone, how great he is, is just a distraction for me. But it is a disappointment that he's not playing out there because obviously it is his event. The crowds love him to death, and he does spice up the event a little bit."
It's the second time in the last seven weeks that Castro got off to a great start. He had a course record-tying 63 on the TPC Sawgrass for a three-shot lead at The Players Championship, and he wasn't sure which was tougher.
"They were totally different rounds," he said. "The one at Sawgrass, I hit it 3 feet eight or nine times. And the one today was more of a normal, lower round where I made some putts. It's hard to compare these two golf courses. That one was playing firm and fast. This one is just long and soft."
DIVOTS: Nick Watney holed out from 148 yards with a wedge on the fourth hole for an eagle on his way to a 70. ... K.J. Choi celebrated his birthday Thursday, at least based on the Korean calendar. The lunar calendar birthday for the 43-year-old was May 19. Either way, here's how Choi counts it: "Every year, I get shorter," he said. ... Every player made at least one bogey.