Hazeltine, Minnesota - Tiger Woods produced a huge statement of intent on Thursday as he carded a flawless five-under-par 67 to set the pace midway through the first round of the US PGA Championship, the final Major of the year.

The world No 1, chasing his 15th Major but his first since the US Open of last year, threw down the gauntlet to his challengers at Hazeltine National, Minnesota, picking up five birdies with not a single bogey on his card as he finished one shot clear of defending champion Padraig Harrington.

A group of players including Robert Allenby of Australia were one shot back on 3-under-par, but the early stages of the event were all about Woods and Harrington, who were paired together.

"I hit the ball well pretty much all day," Woods said. "I didn't make many putts. If I had it could have been a really low number.

"I'm very comfortable with how I'm playing. The way the course is set up, you can be aggressive, make a few more birdies going at the flags."

Woods and Harrington had gone head to head in the final round of the WGC event at Firestone at the weekend and the pair were again the headline attraction.

Beginning at the 10th hole on what is the longest course in Major history, at 7,674 yards, Woods drove the ball beautifully and was out in 34 thanks to birdies at the 12th hole and the 642-yard 15th.

Harrington matched him with birdies at 12 and 16, but a bogey at the first dropped him back to 1-under through 10 holes.

Woods immediately stepped on the gas, picking up birdies at the 2nd and 3rd holes, but Irishman Harrington bounced back with back-to-back birdies of his own.

Harrington then joined Woods on 4-under with a birdie at the 6th hole, but world No 1 Woods birdied the 7th and parred the last two holes to finish on 5-under-par, top of the pile.

Of the other early starters, Englishman Lee Westwood finished on 2-under-par, the same as Graeme McDowell of Northern Ireland, while another Northern Irishman, Rory McIlroy and Sergio Garcia of Spain were tied on 1-under-par after 71s.

World No 2 Phil Mickelson was among the later starters.(dpa)