Golf:KJ Choi knew he was destined for a "special round" even before completing an outstanding six-under-par 64 to move into the lead at the midway point of the AT&T National in Pennsylvania.
Choi managed an unexceptional 69 on Thursday, but was in inspired form on Friday as he matched the course record with four straight birdies on the opening nine setting him on his way.
He made the turn in 30 and, although he bogeyed the 11th, back-to-back birdies on the 15th and 16th ensured he finished his round in top spot on seven under.
Choi, who won The Players Championship earlier this year, said: "I didn't know, nor did anybody tell me (I was on target for the course record). But as I kept making birdies, I noticed that the reactions of the gallery, the people were very positive.
"I started feeling that this was going to be a special round.I think my putter felt good starting from the first hole. I sort of had a trust within myself that I'd be able to play a better front nine [than the first round], and I was able to make five birdies. So I think that was the key."
Choi's passage to the top was eased by struggles for overnight leader Adam Scott, who could only manage a one-over par 71, his afternoon marred by a double bogey on the 14th and bogeys on the third and 17th. Scott will resume at three under on Saturday.
Hunter Haas, co-leader with Scott overnight, shot a 74 to fall to level par.
Choi enjoyed a two-shot lead over Chris Riley, Bo Van Pelt and Charlie Wi, who all went round in 66, while Justin Leonard (67) was also on five under.
Charles Howell, Bryce Molder, Jeff Overton and Kyle Stanley were one shot further back.
Collated second round scores & totals
(USA unless stated, par 70):
133 K J Choi (Kor) 69 64
135 Charlie Wi (Kor) 69 66, Justin Leonard 68 67, Chris Riley 69 66, Bo Van Pelt 69 66
136 Kyle Stanley 67 69, Jeff Overton 71 65, Bryce Molder 69 67, Charles Howell III 68 68
137 Adam Scott (Aus) 66 71, Joe Ogilvie 67 70, Rickie Fowler 68 69
138 Spencer Levin 70 68, Chris Stroud 70 68, John Merrick 68 70, Kevin Na 69 69, Vijay Singh (Fij) 68 70, Bill Haas 68 70, , Troy Matteson 68 70, Jhonattan Vegas (Ve) 67 71
139 Nick Watney 70 69, David Hearn (Can) 69 70, Patrick Cantlay 70 69, William McGirt 72 67, Webb Simpson 69 70, D.A. Points 68 71, Michael Thompson 70 69, J J Henry 70 69, Trevor Immelman (Rsa) 69 70, Robert Allenby (Aus) 71 68, Johnson Wagner 71 68
140 Charley Hoffman 71 69, Robert Garrigus 68 72, Gary Woodland 69 71, Kevin Streelman 71 69, Steve Marino 70 70, George McNeill 70 70, J.B. Holmes 73 67, Dean Wilson 67 73, Hunter Haas 66 74
141 Brendon De Jonge 70 71, Chris Kirk 70 71, Kris Blanks 70 71, Vaughn Taylor 70 71, Chris DiMarco 71 70, Paul Goydos 75 66, Andres Romero (Arg) 71 70, Mike Weir (Can) 71 70, Tom Gillis 72 69
142 Pat Perez 68 74, Bill Lunde 74 68, Tim Herron 71 71, Tag Ridings 70 72, Michael Putnam 72 70, Geoff Ogilvy (Aus) 71 71, Garrett Willis 73 69, Kevin Chappell 70 72, Peter Uihlein 73 69, Kevin Stadler 73 69, Justin Rose 70 72, Cameron Beckman 73 69, Ryuji Imada (Jpn) 72 70, Ryan Moore 72 70, Troy Merritt 74 68, D.J. Trahan 70 72
143 Brian Davis 71 72, Kent Jones 71 72, Rodney Pampling (Aus) 74 69, Scott McCarron 70 73, Steve Flesch 73 70, Michael Connell 74 69, Hunter Mahan 72 71, Ricky Barnes 70 73, Joe Durant 72 71, Carl Pettersson (Swe) 73 70, Stephen Ames (Can) 72 71, Cameron Tringale 75 68
The following players failed to make the cut:
144 Michael Sim (Aus) 73 71, Scott Stallings 69 75, Billy Mayfair 71 73, Brian Gay 69 75, Harrison Frazar 71 73, Ben Curtis 74 70
, Shaun Micheel 73 71, Keegan Bradley 74 70, Billy Hurley III 75 69, Tim Petrovic 73 71, David Mathis 71 73
145 Jason Dufner 72 73, Bobby Gates 73 72, Roland Thatcher 72 73, Camilo Villegas (Col) 74 71, Mark Wilson 74 71, Tommy Gainey 72 73, Josh Teater 72 73
146 Michael Bradley 73 73, Nick O'Hern (Aus) 72 74, Matthew Jones (Aus) 77 69
147 Sean O'Hair 76 71, Greg Chalmers (Aus) 75 72
148 Anthony Kim 73 75, Arjun Atwal (Ind) 77 71, Jim Furyk 77 71, Joseph Bramlett 74 74, Matt Bettencourt 74 74, Chez Reavie 72 76
150 Marc Leishman (Aus) 80 70, Steven Bowditch (Aus) 77 73, Billy Horschel 77 73
151 Jimmy Walker 76 75, Blake Adams 74 77
152 Erik Compton 76 76
153 Zack Miller 73 80, Notah Begay III 74 79, Alex Prugh 77 76
WD: Boo Weekley (USA), Chris Couch (USA)
DQ: Stuart Appleby
