American Brandt Snedeker, who was a total of 25 over par for his three previous Open Championship appearances, stormed to the top of the leaderboard at Royal Lytham & St Annes.
Snedeker carded an opening 66 to lie two shots off the lead held by Australian Adam Scott overnight, but wiped out his deficit in style with a flawless front nine of 30.
The 31 year old from Tennessee picked up shots at the first, sixth, seventh and ninth to match the outward half of Tiger Woods on Thursday, before adding another birdie on the par five 11th to move to nine under and three clear of the field.
Scott, whose opening 64 matched the lowest Open round at Lytham - posted by Tom Lehman on his way to victory in 1996 - had yet to begin his second round, but no one else had been able to mount a sustained move up the leaderboard.
World Number One Luke Donald carded four birdies in five holes from the fourth to be out in 31 and three under, but then fluffed a chip on the tenth to bogey and dropped another shot on the 13th after firing his straightforward approach over the green.
Two bogeys and two birdies kept Rory McIlroy three under after seven holes of his round, but the former US Open Champion then needed two shots to get out of a greenside bunker on the ninth and dropped further shots on the 12th and 14th to lie one over.
That was just one shot inside the current projected cut mark which four-time Major winner Phil Mickelson looked certain to miss, the left-hander at seven over for the tournament with five holes remaining.
England's Greg Owen looked to have found the ideal way to survive for the weekend however, holing his second shot to the 18th for an eagle two and second consecutive round of 71. Owen also had an albatross on the par five 11th when The Open was last staged at Lytham in 2001.
In contrast, Nicolas Colsaerts - who started the day one off the lead - ran up an eight on the seventh and was level par with two holes remaining.
Snedeker picked up his sixth birdie of the day on the 12th to move to ten under and four shots clear, but equally impressive was the fact that he was yet to card a single bogey in the tournament.
Scott dropped a shot on the third to fall back to five under, but 1999 champion Paul Lawrie holed from 15 feet for birdie on the fifth to join former Masters Tournament champion Zach Johnson in second on six under.
Donald completed a 68 to finish two under par, but Padraig Harrington dropped three shots in the last four holes to lie two over and Mickelson completed a 78 to finish 11 over.