Clarke four ahead after 12 holes

Latest positions in the first round of the World Golf Championships-Accenture match play championship at La Costa, Carlsbad, California

(seeded positions in brackets):

(25) Scott Hoch 1 up on (40) Tom Lehman (after 15 holes),

(5) Sergio Garcia 1 up on (60) Kevin Sutherland (14),

(28) David Duval 2 down to (37) Justin Rose (14),

(7) Davis Love 4 up on (58) Paul Casey (13),

(26) Darren Clarke 4 up on (39) Tim Clark (12),

(6) David Toms 2 up on (59) Anders Hansen (12)

(27) Stuart Appleby 1 down to (38) Chris Riley (11),

(16) Justin Leonard 3 up on (49) Jose Maria Olazabal (10),

(17) Bob Estes level with (48) Stephen Leaney (10),

(13) Nick Price 3 up on (52) Paul Lawrie (9),

(20) Charles Howell 1 down to (45) Niclas Fasth (7),

(15) Robert Allenby 2 up on (50) Trevor Immelman (8),

(18) Michael Campbell level with (47) Jeff Sluman (8),

(14) Mike Weir 1 up on (51) Loren Roberts (7),

(19) Jerry Kelly 1 up on (46) Thomas Bjorn (7),

(1) Tiger Woods level with (64) Carl Pettersson (6),

(32) KJ Choi 2 up on (33) Fred Funk (6),

(4) Retief Goosen level with (61) Jay Haas (5),

(29) Shigeki Maruyama level with (36) Scott McCarron (5),

(2) Ernie Els level with (63) Phil Tataurangi (4),

(31) Pet Lonard 2 up on (34) Kenny Perry (3),

(3) Phil Mickelson level with (62) Robert Karlsson (3),

(30) Craig Parry level with (35) Brad Faxon (2)