Johnson stalks down Tiger

Tiger Woods saw his overnight two-shot lead wiped out during the third round at the Northwestern Mutual World Challenge in California.

The world number one had a handy cushion over Zach Johnson after 36 holes of the 18-man tournament, following a scintillating 10-under-par 62.

But he muddled through 10 holes on Saturday in level par, with a birdie at the par-five second hole not proving an accurate sign of what was to come, as he dropped shots at four and eight.

It allowed Johnson to make up ground, and without hitting peak form he joined Woods on 10 under for the tournament by making birdies at holes two and five, dropping a shot at the third.

Former Masters champion Johnson then went into the outright lead by making birdie on nine, but Woods countered with a gain at the next as the pair headed to the 11th tee tied at 11 under.

Woods and Johnson's fellow American Matt Kuchar held third place, two over for his round through 11 holes after following birdies at the opening two holes with four bogeys.

Bubba Watson was alongside him, picking up two shots at the beginning of his back nine after a mixed opening nine holes, while Northern Ireland's Graeme McDowell drifted from five under back to three under after a mixed bag of a performance. Three birdies helped his cause, but a pair of bogeys and a triple at the short eighth hampered his chances.

McDowell could have done with a shot of whatever was powering his compatriot Rory McIlroy, who was looking like producing the day's outstanding round.

McIlroy went round in four-under 68, the only blip being a double bogey at 15. It was too late to thrust him into contention, with a 73 followed by Friday's 77 leaving the 24-year-old well off the pace. Four under for the day placed him two over for the tournament, down in 12th place.