ARDMORE, Pa. (AP) -- Play has been suspended for the day at the U.S. Open, with Phil Mickelson and Billy Horschel tied for the lead.
Mickelson birdied the 18th late Friday to finish a 2-over round of 72. Horschel shot 3-under 67, hitting all 18 greens in regulation at Merion Golf Club.
Their 1-under totals of 139 made them the only players under par for the tournament; nearly half the field had yet to complete the second round, which was halted because of darkness.
Luke Donald, Steve Stricker and Justin Rose were in the clubhouse at even par. Two other players were still on the course at even par.
The second round began late in the morning because storms on Thursday forced half the field to return early Friday to finish the first round.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
Billy Horschel hit all 18 greens in regulation. Hard to think of a better way to climb to the top of the leaderboard at the U.S. Open.
He shot 3-under 67, sufficiently managing the nasty rough and hard-to-read greens to become the clubhouse leader late in the second round Friday at the Merion Golf Club.
Horschel was 1 under with a 139 total, posting one of the few red numbers on a trying day for much of the field. He missed the cut in his only previous U.S. Open, in 2006, but recently won for the first time on the PGA Tour at the Zurich Classic.
"I've acquired some patience, not as much as I wish I had," said the 26-yeaar-old from Jacksonville Beach, Fla. "But I just think that the older I get, the more mature I get on the golf course, the more understanding that if I do have a bad stretch of holes, it's not that I don't hit the panic button, I just don't press right away."
Phil Mickelson held the solo lead for much of the afternoon, but he missed birdie chances during a streak of 10 consecutive pars. He then 3-putted No. 12 for a bogey and dropped another stroke when he put his tee shot in the sand on the short par-3 13th, the easiest hole on the course.
Seconds later, Steve Stricker, playing in Mickelson's group, sank a birdie putt from about 15 feet to move into a tie with Horschel for the lead. Justin Rose was also at 1 under on the back nine.
Hoping to build on his own 67 from Thursday, Mickelson put his first shot in a bunker and 3-putted the first hole for a bogey. He was in rough and sand at No. 2, but he recovered to start the run of pars, avoiding even the distraction of a groundhog - a relative of Punxsutawney Phil? - who made a mad dash across the fairway at No. 6. Mickelson lipped out a 4-foot birdie putt at No. 8.
A five-time runner-up seeking his first U.S. Open title, Mickelson had the luxury of a late tee time, much needed after he showed up with just a few hours to spare for the opening round so he could attend his daughter's eighth-grade graduation in California. It turned out to be a gift. While Mickelson was able to rest Friday morning, much of the field endured the ordeal of finishing a delayed first round followed by a second round with little break in between.
By the time Mickelson teed off, only he and Belgium's Nicolas Colsaerts were under par. Colsaerts shot a 69 in the first round, but he fell off the pace Friday with three bogeys on the front nine.
As for the weather, the sun stayed around for most of the afternoon after play began in a cool drizzle that was far gentler than the storms that interrupted play twice on Thursday. The fallout from all the rain was a cramped schedule, complicated because the course requires long shuttle rides to move the players to and fro. It also left players and spectators spackled in mud from their shoes on up.
The must-see group of Tiger Woods, Adam Scott and Rory McIlroy was at times a hard-to-watch bunch - perhaps even for Woods' ski champion girlfriend Lindsey Vonn, who was part of the gallery.
The trio combined to shoot 14 over at the halfway mark. Woods' troublesome left elbow flared up again, and he hit a chip from just off the green that traveled barely a foot while making bogey at the par-4 7th.
Woods then dropped his left hand off the club and shook his wrist while putting his tee shot wide of the fairway at No. 8, just as he had done several times on Thursday. The arm clearly bothered him again on the next shot, which he put in the rough near the green. He saved par on the hole and finished a second-round 70 that left him at 3 over for the tournament, still in contention if he can stay healthy.
"It's hard with the wind and the pin locations," Woods said. "They're really tough. ... We didn't think they were going to be as severe as they are."
Woods was tight-lipped about his elbow, saying only that it first bothered him at the Players Championship five weeks ago. Asked what he felt, he answered: "Pain."
Masters champion Scott fell apart quickly, all but quashing any hope for a Grand Slam. He was 3 under when first-round play was suspended Thursday, but he hit a hard-luck Merion shot at No. 12: an approach that landed just short of the pin, spun backward and rolled some 75 feet to the edge of the fairway rough. He also put a tee shot out of bounds at No. 14 to complete a first-round 72, then came back after the short turnaround to post a 76, 8 over, through two rounds.
"I got off on the wrong foot and just struggled to find my rhythm all day," Scott said. "I didn't make the putts I needed to kind of save some shots here and there. And they just slipped away too easily. But that's what can happen if you're just a little bit off."
McIlroy had quite the adventure, putting his drive at No. 4 onto the No. 8 fairway. Once he got back to the correct hole, he put a shot in a bunker and bogeyed the par 5. His second-round 70 left him at 3 over.
"I'm very happy. Right in there for the weekend," McIlroy said. "I don't think I'll be too far away by the end of the day."
Then there was Luke Donald, who actually pulled ahead of Mickelson at 4 under with back-to-back birdies, including a chip-in at the par-3 13th during his second round. But Merion took him apart on the front nine when he bogeyed four consecutive holes, turning his number from red to black. His second-round 72 left him at even-par.
Coming into the Open, the question was how Merion would fare against a modern-day championship field. It last hosted this event in 1981, with the thinking that today's golfers had outgrown the course.
Certainly, the 301-yard par-3 10th and 102-yard par-3 13th yielded their share of makeable shots, but pre-tournament concerns about scores in the low 60s seem totally unwarranted.
"It's very difficult to make those putts," Donald said, "when the ball is breaking so much."
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