Woods under pressure

Woods had begun the fourth round at a rain-softened Hazeltine National with a two-shot lead at eight under par over Korean Yang and defending champion Padraig Harrington of Ireland.

Yang upped the ante with a birdie at the par-five third and Woods folded at the par-three fourth, three-putting for bogey to fall into a tie with the Korean at seven under.

Yang's time in the lead was short-lived as he bogeyed the fifth, while Harrington narrowly missed birdie chances at the fifth and sixth to stay tied for second at six under.

A third of an inch of rain had fallen overnight on the 7,674-yard, par-72 Minnesota course after Woods completed a third-round 71 to close in on a record-tying fifth US PGA title.

Playing conservative, low-risk golf, the world number one had seen his four-stroke halfway lead cut in half by Yang's five-under 67 and Harrington's 69.

Also within reach of Woods, winner of his last two tournaments, was Henrik Stenson of Sweden and American US Open champion Lucas Glover, a further two shots in arrears at four under par with Denmark's Soren Kjeldsen and Ernie Els of South Africa at three under.

Woods was paired with Yang for the final round with Harrington partnering Ryder Cup team-mate Stenson in the penultimate group out, and also had history on his side having converted all 14 of his 54-hole major leads into victories.

Glover made an early charge, getting to six under after birdies at the third and fifth but bogeying the sixth.

England's Lee Westwood picked up two shots to reach three under after 12 holes, while Northern Ireland's Rory McIlroy rebounded from a double bogey six at the first with birdies at the third, fourth, fifth and ninth to also get to three under.