At nine-under 131 overall, Pernice is tied at the top of the leaderboard with Jeff Overton, who shot a bogey-free 65.

Anthony Kim is in third at six-under 134 after carding his second consecutive 67, while a group of seven players are at five under, including Steve Stricker and John Merrick, who shot 64s, and first-round leader Steve Marino, who signed for an even-par 70.

Pernice played his first five holes on the Blue Course at Congressional Country Club in even par before catching fire, starting a string of four straight birdies at the par-four sixth.

He added three birdies on the back nine, including one to close his round at the par-four 18th.

It marked the second time this year Pernice has shot a 63. He also reached that number in the final round of the St Jude Championship last month en route to tying for eighth.

Winless on the PGA Tour since claiming The International in 2001, Pernice missed the cut last week at the Buick Open.

Defending champion KJ Choi fell eight shots back of the leaders after a one-over 71 dropped him to one-under 139 and a tie for 26th.

The event is hosted by Tiger Woods, who was advised by doctors not to fly after undergoing knee surgery to repair a torn anterior cruciate ligament in his left knee three weeks ago.

Collated second round scores & totals in the USPGA Tour AT&T National, Congressional G & CC, Bethesda, Maryland, United States of America

(USA unless stated, par 70):

131 Jeff Overton 66 65, Tom Pernice Jnr. 68 63

134 Anthony Kim 67 67, Cliff Kresge 69 65

135 Steve Stricker 71 64, Steve Marino 65 70, Jeff Maggert 70 65, Rodney Pampling (Aus) 66 69, John Merrick 71 64, Billy Mayfair 67 68, Nick O'Hern (Aus) 70 65

136 Patrick Sheehan 69 67, Tommy Armour III 67 69

137 Robert Allenby (Aus) 68 69, Jose Coceres (Arg) 69 68, Todd Hamilton 70 67, Parker McLachlin 71 66

138 Pat Perez 71 67, Robert Garrigus 68 70, Tim Herron 68 70, Michael Allen 70 68, Alex Cejka (Ger) 67 71, John Rollins 68 70, Jim Furyk 70 68, Johnson Wagner 70 68

139 Brad Adamonis 68 71, John Senden (Aus) 70 69, Fred Funk 70 69, Fred Couples 71 68, Kevin Streelman 69 70, Dean Wilson 69 70, Bob Estes 66 73, Fredrik Jacobson (Swe) 67 72, KJ Choi (Kor) 68 71, Bo Van Pelt 70 69, Rich Beem 71 68, Olin Browne 69 70, D.J. Trahan 71 68, Jesper Parnevik (Swe) 68 71

140 J J Henry 73 67, Bill Haas 70 70, Corey Pavin 73 67, Todd Demsey 70 70, Gavin Coles (Aus) 69 71, Kevin Sutherland 69 71, Charles Howell III 70 70, Frank Lickliter II 66 74

141 Brian Davis (Eng) 72 69, Nick Watney 69 72, Charles Warren 69 72, Hunter Mahan 69 72, J.B. Holmes 70 71, Ben Crane 71 70, Joe Durant 70 71, Jim McGovern 68 73, Camilo Villegas (Col) 71 70, Rocco Mediate 73 68, Jonathan Byrd 70 71, Shane Bertsch 72 69, Stuart Appleby (Aus) 67 74

142 Eric Axley 69 73, Lucas Glover 71 71, Andres Romero (Arg) 71 71, Stephen Leaney (Aus) 71 71, James Driscoll 73 69, Matthew Jones (Aus) 74 68, George McNeill 68 74, Justin Bolli 74 68, Tim Clark (Rsa) 73 69

143 Arron Oberholser 72 71, Charley Hoffman 73 70, Vaughn Taylor 70 73, Joe Ogilvie 76 67, Davis Love III 70 73, Mathias Gronberg (Swe) 74 69, Peter Lonard (Aus) 74 69, Mark Wilson 70 73, Tim Wilkinson (Nzl) 71 72, Billy Andrade 70 73, Sean O'Hair 72 71, Cameron Beckman 75 68, Ryan Armour 72 71, Nicholas Thompson 76 67

--------------------Following players failled to make the cut-----------------------

144 Steve Flesch 74 70, Marco Dawson 73 71, Steve Lowery 75 69, Matt Kuchar 74 70, John Mallinger 74 70, Chez Reavie 75 69, Charlie Wi (Kor) 73 71, Kevin Stadler 77 67, Trevor Immelman (Rsa) 73 71, Ryan Palmer 77 67, Notah Begay III 67 77, Brandt Snedeker 72 72

145 Dudley Hart 73 72, Chris Riley 74 71, Brian Gay 72 73, Troy Matteson 75 70, Jason null Day (Aus) 71 74

146 Will MacKenzie 77 69, Brett Rumford (Aus) 73 73, Jeff Quinney 75 71, Ryuji Imada (Jpn) 74 72, Drew Weaver 75 71

147 Ryan Moore 75 72

148 Mike Weir (Can) 72 76, J.P. Hayes 72 76, Greg Kraft 76 72

149 Mathew Goggin (Aus) 73 76, Tim Petrovic 73 76, Tag Ridings 74 75

150 Bart Bryant 73 77, Lee Janzen 78 72

153 Ken Duke 78 75