Brandt Snedeker matched the lowest 36-hole total in Open history to take a one-shot lead at the halfway stage at Royal Lytham & St Annes.
The American added a 64 to his opening 66 for 10 under to edge past first-round leader Adam Scott (67) with Tiger Woods (67) four back after chipping in at the last.
Snedeker emulated Scott from day one as he tied the course record for an Open at Lytham and has yet to drop a shot or find one of the 206 bunkers this week.
The 31-year-old's two-round total of 130 equals Nick Faldo's record set at Muirfield in 1992.
Denmark's Thorbjorn Olesen, 22, finished with a 66 for five under on his own in late evening sunshine after a day of mainly dry weather and modest breeze on the Fylde coast.
Scotland's Paul Lawrie (71), Northern Ireland's Graeme McDowell (69), Americans Jason Dufner (66) and Matt Kuchar (67) and South African Thomas Aiken (68) all finished four under.
South Africa's Ernie Els, the 2002 champion, ended three under after a 70.
World number one Luke Donald shot 68 to edge to two under alongside fellow Englishman James Morrison (70), American Steve Stricker (71) and New Zealander Steven Alker (69).
Northern Ireland's second-ranked Rory McIlroy carded a five-over 75 to slide to two over, the same score as Padraig Harrington, while world number three Lee Westwood made the cut with no room to spare after a level-par 70 left him three over.
World number 29 Snedeker, who had six birdies and six straight pars to finish, has missed the cut at his previous three Opens.
"I'm sure everybody in this room is in about as much of shock as I am right now," he said in his post-round news conference.
"My mantra all week has been to get the ball on the greens as fast as possible. Once I'm on there I have a pretty good handle on the speed of the greens.
"I'm just going to try and keep doing that over the weekend."
Scott, who was 32 on Monday, dropped a shot at the third but hit back with birdies at the seventh, 10th, 11th and 18th to stay in the hunt.
"It's a world-class leaderboard and I think no matter what conditions are one of those guys is going to have a good day and make up ground," he said. "Brandt and myself certainly have our work cut out to stay ahead of the pack."
Woods, who only hit one driver all day - on the second - dropped a single shot on the 11th but birdies at four, six, 16 and 18 edged him closer.
"I figured I had a game plan that I thought would fit well on this golf course, and I figured I could execute it and I've done that so far," said the 14-time major champion, who finished with a spectacular birdie from a bunker at the last.
Donald kept himself in contention by swapping three bogeys for five birdies, including three in a row from the fourth.
"Again, it was a pretty solid round, tee to green," said Donald, who was without regular caddie John McLaren as he dashed to London to attend the birth of his first child. "The difference between yesterday's and today's round was I holed a few more putts.
"I'm certainly feeling more and more comfortable. Obviously where I am in my career I need to be contending."
Five-time Open champion Tom Watson birdied the last to book his place for the weekend, but Sergio Garcia and Justin Rose were among 17 players who missed the cut after finishing on four over.
Defending champion Darren Clarke carded 71 to finish seven over, while American Phil Mickelson (78) and England's Paul Casey (79) both finished on 11 over par.