Long-hitting American J.B. Holmes posted an early two-under-par 68 to claim a one shot lead after two rounds of the PGA Championship.
Justin Rose, Charlie Wi and Ben Curtis were tied at level-par 140, one better than David Toms and Henrik Stenson on the tough Oakland Hills layout which was playing lightning fast.
The top six on the leaderboard all had morning tee times when the conditions were more favourable.
Padraig Harrington, on five-over, heads the Irish challenge.
Holmes began at one over par, three shots off the pace, and made the turn at level par before a string of three birdies starting at the par-five 12th lifted him to three under par.
The stocky 26-year-old from Kentucky dropped two strokes with bogeys at the 15th and par-three 17th hole but the twice PGA Tour winner did enough to post the only sub-par total through 36 holes.
"I played great. I hit the ball well," Holmes told reporters. "I left a few putts out there, but overall it was a very good ball-striking round."
Three shots behind Holmes was a group of seven including 2007 U.S. Open champion Angel Cabrera, Sergio Garcia, Aaron Baddeley and Jeev Milkha Singh of India, the overnight co-leader who posted a 74.
Phil Mickelson, a three-times major winner, was another shot back in a large group four strokes off the pace.
Collated second round scores
(USA unless stated,
Irishin bold, par 70):
139 J.B. Holmes 71 68
140 Charlie Wi (Kor) 70 70, Justin Rose (Eng) 73 67, Ben Curtis 73 67
141 David Toms 72 69, Henrik Stenson (Swe) 71 70
142 Jeev Milkha Singh (Ind) 68 74, Aaron Baddeley (Aus) 71 71, Sean O'Hair 69 73, Sergio Garcia (Spa) 69 73, Ken Duke 69 73, Angel Cabrera (Arg) 70 72, Brandt Snedeker 71 71
143 Phil Mickelson 70 73, Paul Goydos 74 69, Steve Flesch 73 70, Boo Weekley 72 71, Briny Baird 71 72, D.J. Trahan 72 71, Nicholas Thompson 71 72
144 Peter Hanson (Swe) 71 73, Michael Campbell (Nzl) 73 71, Brian Gay 70 74, Tom Lehman 74 70, Steve Elkington (Aus) 71 73
145 Robert Karlsson (Swe) 68 77, Justin Leonard 74 71, Anthony Kim 70 75, Rory Sabbatini (Rsa) 72 73, Michael Allen 70 75, Alastair Forsyth (Sco) 73 72, Ian Poulter (Eng) 74 71, Carl Pettersson (Swe) 71 74, Padraig Harrington71 74
146 Steve Stricker 71 75, Pat Perez 73 73, Graeme McDowell74 72, Retief Goosen (Rsa) 72 74, Mark Brown 77 69, Dean Wilson 73 73, Paul Casey (Eng) 72 74, Fredrik Jacobson (Swe) 75 71, Niclas Fasth (Swe) 73 73, Ernie Els (Rsa) 71 75, Prayad Marksaeng (Tha) 76 70, Camilo Villegas (Col) 74 72, Stuart Appleby (Aus) 76 70
147 Charl Schwartzel (Rsa) 77 70, Billy Mayfair 69 78, Chris DiMarco 75 72, Geoff Ogilvy (Aus) 73 74, Andres null Romero (Arg) 69 78, Kevin Sutherland 76 71, John Mallinger 72 75, Hiroyuki Fujita (Jpn) 77 70, Steve Marino 73 74, Mark Calcavecchia 71 76, Rocco Mediate 73 74
148 James Kingston (Rsa) 72 76, John Merrick 73 75, Paul Azinger 72 76, John Senden (Aus) 76 72, Bubba Watson 75 73, Louis Oosthuizen (Rsa) 76 72, Peter Lonard (Aus) 74 74, Chez Reavie 78 70, Charles Howell III 72 76, Robert Allenby (Aus) 76 72, Jim Furyk 71 77, Mike Weir (Can) 73 75, Richard Green (Aus) 71 77, Corey Pavin 75 73, Tim Clark (Rsa) 76 72
The following players failed to make the cut
149 Zach Johnson 76 73, Soren Kjeldsen (Den) 75 74, Todd Hamilton 76 73, Brendan Jones (Aus) 71 78, Simon Dyson (Eng) 73 76, Tom Pernice Jnr. 75 74, Fred Couples 76 73, Bob Tway 75 74, John Daly 74 75, Frank Esposito 71 78, Rich Beem 73 76, Johnson Wagner 78 71, Ryan Moore 70 79
150 Vaughn Taylor 78 72, Adam Scott (Aus) 77 73, Nick O'Hern (Aus) 74 76, J J Henry 76 74, Daniel Chopra (Swe) 74 76, Richard S Johnson (Swe) 75 75, Jay Haas 73 77, Mark Brooks 74 76
151 Rodney Pampling (Aus) 70 81, Anders Hansen (Den) 75 76, Steve Lowery 74 77, Scott Strange (Aus) 73 78, Stewart Cink 75 76, Darren Clarke75 76, Heath Slocum 74 77, Don Yrene 75 76, KJ Choi (Kor) 78 73, Miguel Angel Jimenez (Spa) 73 78
152 Hennie Otto (Rsa) 76 76, Alan Morin 76 76, Davis Love III 77 75, Tommy Armour III 79 73, Vijay Singh (Fij) 76 76, Chad Campbell 76 76, Stephen Ames (Can) 77 75, Jyoti Randhawa (Ind) 77 75
153 Jerry Kelly 79 74, Tim Weinhart 74 79, Ross Fisher (Eng) 77 76, Trevor Immelman (Rsa) 76 77, Soren Hansen (Den) 77 76, Parker McLachlin 76 77, Sonny Skinner 78 75
154 Steve Webster (Eng) 78 76, Bart Bryant 77 77, Sam Arnold 80 74, Martin Kaymer (Ger) 75 79, Toru Taniguchi (Jpn) 79 75
155 Jim Estes 79 76, Ben Crane 75 80, Ryan Benzel 77 78, George McNeill 78 77, Oliver Wilson (Eng) 78 77, Cliff Kresge 83 72, Lee Westwood (Eng) 77 78, Scott Verplank 77 78
156 Mathew Goggin (Aus) 81 75, Jeff Quinney 81 75, Rick Leibovich 78 78, Peter Hedblom (Swe) 76 80, Scott Hebert 80 76
157 Tim Thelen 81 76, Ryuji Imada (Jpn) 80 77, Jeffrey W Martin 78 79, Greg Kraft 78 79, Jonathan Byrd 75 82
158 Curt Sanders 78 80, Kyle Flinton 79 79, Woody Austin 79 79, Brad Martin 77 81, Pablo Larrazabal (Spa) 80 78
159 Nick Dougherty (Eng) 77 82
160 Hunter Mahan 81 79, Colin Montgomerie (Sco) 76 84
161 Eric Dugas 87 74
162 David Long 80 82
163 Vince Jewell 85 78
169 Eric Manning 81 88
170 Bradley Dean 86 84