Four ahead of the pack overnight, the world No 1 fired a five-under-par 67 at Sherwood Country Club for an 18-under total of 198.

Although not matching his blistering form of Friday when he set a course-record 62, he carded seven birdies in pursuit of his fourth title in the elite 16-man tournament he hosts.

Playing partner Jim Furyk slipped back with a double-bogey at the par-three 15th on his way to a 69 and second place. Masters champion Zach Johnson also carded a 69 to lie third at 11-under, one ahead of Swede Henrik Stenson who fired a best-of-the-day 65.

Woods birdied the first two holes on a second successive day of calm weather. The 13-time major winner coolly rolled in a 15-footer at the par-four first before enjoying a slice of good fortune with his drive at the par-five second.

He pulled his tee shot well left of the fairway, his ball striking a young boy above the right hip before bouncing back into the rough. After laying up safely with an iron on to the fairway, the 31-year-old American struck a superb wedge to within two feet of the flag to set up a tap-in birdie.

Woods offset birdies at the fifth and sixth with bogeys at the fourth and eighth for his lead to be trimmed to three strokes.

However, he picked up further shots at the 10th, where he hit an exquisite low, hooking approach to a foot, and at the par-five 11th, where he drained a 15-foot putt, to forge four ahead.

Leading scores (after 54 holes): 198: Tiger Woods (69, 62, 67); 204: Jim Furyk (68, 67, 69); 205: Zach Johnson (69, 67, 69); 206: Henrik Stenson (Swe, (69, 72, 65); 209: Steve Stricker (72, 69, 68), Vijay Singh (72, 68, 69); 211: Lee Westwood (72, 71, 68), Paul Casey (72, 67, 72); 212: Mark Calcavecchia (71, 71, 70).