Overnight leader Darren Clarke shot a 1-under 71 and is tied for third with Ernie Els (70) and Briny Baird (69). The trio is knotted at 8-under-par 136.
Tiger Woods' PGA Tour record of 128 consecutive cuts made was in serious jeopardy on Friday. He birdied the 16th and 17th holes to shoot a 69 and make the cut by a shot at even-par 144.
The last time Woods failed to make a cut was the 1998 Pebble Beach National Pro-Am. The tournament was reduced to 54 holes and due to weather problems, the final round was pushed from early February to mid-August. He did not return for the final round, so he failed to make the cut.
The Canadian Open in September of 1997 was the last time Woods missed the 36-hole cut in a traditional sense.
At last year's Tour Championship, Woods eclipsed Byron Nelson's 55-year-old record of 113 consecutive cuts. He made the first 14 cuts this season, but a terrible round of driving nearly cost Woods his first missed cut in a major since turning professional in 1996.
Woods started the second round at 3 over par and the projected cut line looked like plus-1. He opened Friday's second round with a 3-foot birdie putt that came from a beautiful approach out of the first cut of rough. Woods added a two-putt birdie at the par-5 second to get to 1-over, but trouble loomed for the two-time PGA Champion.
Woods found the water off the tee at the par-5 fifth and took his drop, then a questionable path to the green. He hit a 3-wood from the thick rough into thick rough near the putting surface. Woods pitched 40 yards right of the green, then hit his fifth to 5 feet. He holed that putt for bogey, then missed an 8-footer to save par at the sixth.
He continued to miss fairways, but scrambled for pars. Woods sank a 4-footer for par at the 15th and split the fairway at the par-5 16th. Woods' 6-iron from 207 landed 45 feet right of the hole and his eagle putt skimmed the hole on the left side. He ran home the 3-footer for birdie to get to the number.
Woods tacked on another birdie at the 17th when he got a great read from playing partner Singh's birdie putt. Woods rolled in the 20-footer to reach even-par for the championship.
The No. 1 player in the world for 331 weeks ripped his drive down the fairway at the last. Woods hit his second in the right rough, pin-high but gave himself very little green to work with. He pitched 4 feet short of the hole and converted the par putt to keep his hopes alive of breaking a major drought that dates back to the 2002 U.S. Open.
'I got off to the greatest start you could possibly have,' said Woods, who is now at 129 consecutive cuts and counting. 'I threw those shots away real quick. I wasn't playing very well. I had to keep trying to make pars.'
With the Woods drama out of the way, Leonard and Singh, who played with Woods in the first two rounds, stole the show at a Whistling Straits course that played more difficultly than in round one.
The wind blew harder and the course played more to the length that made it the longest course in major championship history.
Leonard began on the back nine Friday and wasted little time in getting into red figures. He rolled in a 25-foot birdie putt at the 10th, then missed a 7-footer for par at No. 12.
The 1997 British Open champion kicked in a short birdie putt at the par-5 16th and sank an 8-foot birdie putt at the first. Leonard hit a 7-iron to 20 feet at the third and made the putt for his fourth birdie of the round and a share of the lead at 9 under.
Leonard drove in a fairway bunker at the fourth and laid up short of the putting surface. His third landed 10 feet from the hole, but Leonard missed the par putt to fall from first. He hit a pitching-wedge to 2 feet at the next hole to reclaim his share of the lead.
'I felt like I played pretty solid today, not quite as well as yesterday, but still it was a good day,' said Leonard, who held the 54-hole lead of the PGA Championship in 2002. 'I'm just glad to shoot a couple of good rounds and be in good position going into this weekend.'
Singh, the 1998 winner of the Wanamaker Trophy, did not get off to a great start on Friday. He hit a horrible drive, then three-putted from 45 feet for a bogey.
He drained an 8-footer for birdie at two, then tallied back-to-back birdies at four and five. Singh hit a sand-wedge to 15 feet on No. 10 to set up birdie and get to 8 under for the championship. He knocked an 8-iron to 5 feet for another birdie at 14 and a share of the lead.
Singh quickly lost his piece of first. His drive at 15 landed in the bunker, then his 6-iron went left. Singh chipped to 20 feet and two-putted for a bogey, falling one behind Leonard.
Singh, who won the Masters in 2000, reached the green in two with a 5-iron at the par-5 16th. He two-putted from 25 feet for birdie, then nearly holed a 90-foot putt at the last that would have given him first by himself.
'I'm going to try my hardest to win this one,' said Singh, who has four wins in 2004, including a title at the Buick Open two weeks ago. 'Not winning from 2000, obviously I'm disappointed that I have not won any more majors, but there's always the next one. I always keep telling myself that, and this is another good opportunity right here.'
Clarke, who played with Leonard on Thursday and Friday, double bogeyed the 11th, his second, but tallied four birdies over his next 12 holes. He made a mess of the sixth and bogeyed the hole, then drained a 60-footer for birdie at No. 7. Clarke lipped out a 4-footer for par at eight to fall one of the lead.
Els built a two-stroke lead with four birdies over his opening 10 holes. He drove into the tall grass on the left side at 11 and made bogey.
This year's runner up at the Masters and British Open hit his tee ball in the left rough at the par-5 16th. His second went farther left into a bunker and all Els could do was play his third into another sand trap closer to the green. Els blasted that shot 35 feet past the stick and two-putted for a bogey that dropped him into the share of second.
Baird played in the morning and recorded four birdies in his first seven. He went 1-over the rest of the way, but is in position for not only his first major, but victory No. 1 on the PGA Tour.
'I can't come in thinking I've got a great shot at winning, because the fact of the matter is, Ernie has a better chance of winning this golf tournament than I do, or Tiger or Vijay,' said Baird. 'They have done it, and I'm still sitting here hoping to talk to you guys on Sunday. Until I do it, it's hard for me to say that.'
Chris DiMarco holed out for an eagle at the 14th en route to a 2-under 70. He is alone in sixth at minus-6, followed by Stephen Ames (71), K.J. Choi (71), Padraig Harrington (71) and Chris Riley (70). That group finished two rounds at 5-under-par 139.
Reigning Masters champion Phil Mickelson shot an even-par 72 and is part of a group tied for 13th, along with Miguel Angel Jimenez, who fired the low round of the day with a 7-under 65. Mickelson and Jimenez headline a logjam at minus-3.
Defending champion Shaun Micheel rebounded with a 4-under 68 on Friday and made the cut at 1-over-par 145. Among the notable players who will not be around on the weekend are: Sergio Garcia (146), Mike Weir (146), Davis Love III (148), Jim Furyk (153) and Ryder Cup hopeful Jerry Kelly (153).