Northern Trust Open:World number two Phil Mickelson carded a seven-under-par 64 to take a four-shot lead after the second round of the Northern Trust Open at Riviera Country Club in California.
The left-hander posted nine birdies and two bogeys as he raced to 10 under par, leaving his rivals trailing in his wake.
Americans Jeff Quinney and Vaughn Taylor and Australian Robert Allenby are joint second, while although Open champion Padraig Harrington improved his standing with a second successive two-under 69, he fell further off the pace.
The Irishman's Ryder Cup team-mate Luke Donald began the day alongside Mickelson in joint fifth but a level par round saw him drop down to a share of 13th on three under.
Paul Casey shot a 70 to move to one over and make the cut — a feat not achieved by fellow Englishmen Justin Rose , Lee Westwood and Brian Davis.
Rose could only follow his opening 72 with a 75 to drop to five over, with Westwood finishing 10 over after a 78 and Davis nine over after a 77.
