Tiger makes move in California

Tiger Woods was a man on the move midway through the second round of the Northwestern Mutual World Challenge in California.

After shooting a one-under-par round on the opening day, the world number one hit five birdies over the first nine holes to reach the turn in 31.

That left Woods on six under, two strokes behind leader Zach Johnson, who shot a five-under 67 on Thursday and was three under through six holes of his second round at the Sherwood County Club.

Woods' day-two efforts were a far cry from his opening round, which began with a bogey on the first before he made gains at five and 11. Twenty-four hours on Woods kicked off with a birdie at the first, repeating the trick on the second hole before further gains at five, seven and eight.

Johnson appeared in no mood to relinquish his lead, however, and mirrored Woods' efforts over his first six holes to remain firmly at the head of the pack.

Matt Kuchar was also three under through six holes on Friday, keeping him within one stroke of the lead at seven under.

Elsewhere, Northern Ireland's Graeme McDowell was the best-placed of the British contingent in eighth place on two under par, having picked up two birdies through nine holes after opening with a par 72.

England's Ian Poulter was four under through 13 holes but that was only good enough for even par overall after his disappointing 76 on Thursday.

Rory McIlroy was also struggling, going one over through 10 after signing for 73 on his first round, while England's Lee Westwood was having a nightmare round, conceding bogeys at six and 11 and a double-bogey at seven to drop to six over par overall.