U.S. Open champion Webb Simpson fired a 4-under 66 on Friday to take the lead at the Greenbrier Classic.

However, the event's second round was not completed because of inclement weather in the afternoon that forced a delay of more than two hours. Play resumed in the early evening, but 15 players weren't able to complete their rounds before darkness fell.

Second-round play will resume Saturday at 8:30 a.m. (et).

Simpson was able to get through his 18 holes on the Old White TPC Course at The Greenbrier, and is the clubhouse leader at 9-under-par 131.

Charlie Beljan had fired an 8-under 62 in the morning to climb to the top of the leaderboard at minus-8. He was bumped down by Simpson, and shares second with Jonathan Byrd (68), Jeff Maggert (68) and Jerry Kelly (66). Martin Flores, who was 2-under through 16 holes of his second round, is also at 8- under for the championship.

Two players who won't see the weekend are Tiger Woods and Phil Mickelson.

Woods, last week's winner at the AT&T National, shot a 1-under 69, but that wasn't enough for him to recover from an opening 71. He finished 36 holes at even-par 140, one stroke below the projected cut.

"I didn't quite have it," Woods said. "I drove it really good today and I just did not have the feel for the distances. The ball was just going forever."

Mickelson carded a second consecutive 1-over 71 to fall to plus-2.

First-round leader Vijay Singh struggled to a 4-over 74 to finish two rounds at 3-under 137.

Beljan, a PGA Tour rookie, began on the back nine Friday and poured in four birdies before making the turn. But his success on the front nine had him flirting with a 59.

He found the fairway rough at the first hole, but dropped his approach within nine feet of the pin and made the putt. Then, at the second, he stuck the approach three feet from the flag and rolled in the easy birdie to get to minus-6.

Back-to-back birdies at the fourth and fifth -- putts of 14 and five feet, respectively -- pushed him to 8-under, and another at the seventh pushed him further below par.

Beljan needed a birdie-birdie finish to get the 59, and didn't come close. He parred the eighth before ending with a bogey. Still, the round had him at the top of the leaderboard.

"Today was the best day of my career," Beljan said. "It was wonderful from the first hole, making birdie, to the last hole I made bogey, but it still didn't matter."

Byrd went off the first tee in the morning wave and also reached minus-8, though three bogeys in a four-hole stretch from the eighth marred his round.

Maggert, who was tied with Byrd and Flores for second place after the first round, began his round with a bogey but played clean golf the rest of the way. He birdied three and nine, then sank one at the last to settle at 8-under.

Kelly fired four birdies during a flawless round to get to that number.

By the end of the day, Simpson had passed them all. He parred his first six holes before dropping in birdies at seven and eight, where he holed an 18- footer.

Those put him at 7-under heading around the turn, and Simpson picked up another stroke at the 12th to join the logjam at minus-8.

But at the last, a par-3, Simpson pushed ahead. He hit his tee shot within six feet, then made the putt.

Flores, who had one bogey and three birdies in his first 16 holes, can tie or surpass Simpson when he gets back on the course Saturday morning. He's the only player in the top 23 who has yet to complete his second round.

J.B. Holmes (68) and Charlie Wi (66) are tied for second place at 7-under 133, while five players share ninth -- Bob Estes (65), Scott Piercy (68), Billy Mayfair (65), Ken Duke (68) and Sean O'Hair (68).

NOTES: Hall of Famer Tom Watson, The Greenbrier's golf professional emeritus, shot a 68 on Friday to get to 2-under and make the cut...Among players who will miss the cut are Jim Furyk and Rory Sabbatini (even-par 140), as well as 2010 champion Stuart Appleby (143).