AUGUSTA, April 7: Former winner Vijay Singh rattled up four birdies in five holes to take charge in the U.S. Masters first round on Thursday while holder Tiger Woods ground out a level-par 72.

Champion in 2000, Singh picked up shots at the 11th, 13th, 14th and 15th for an opening five-under 67 in difficult conditions at a sun-baked Augusta National.

That left the Fijian one ahead of American Rocco Mediate, who birdied the same stretch of holes in a blemish-free display.

“I played pretty decent today and didn't make too many mistakes,” world number two Singh told newsmen. “I had a lot of chances early on and I putted very well.

“That was probably one of the better rounds I've played here.”

Another American, Arron Oberholser, opened with a 69 to finish a stroke better than world number three Retief Goosen and fellow South African Tim Clark.

Mediate, a five-times winner on the PGA Tour, was delighted to be back at a challenging venue where he feels comfortable.

“It was fun, I had a blast today,” said a smiling Mediate. “I putted better today than I may ever have putted here.”

World number one Woods, chasing a fifth green jacket, moved to one under by spectacularly holing an eight-iron from the fairway for an eagle-two at the 14th.

However, he then ran up a double-bogey seven on 15, where he found water with his approach, before finishing in style with a 35-foot birdie putt at the last.

Of the other big names in the first major of the year, 2003 champion Mike Weir opened with a 71 while former world number one David Duval slumped to an 84, his worst round at Augusta.

Left-hander Phil Mickelson, the 2004 champion, was at even par after 12 holes, a stroke better than playing partner Ernie Els.

Twice winner Ben Crenshaw, who has not made the cut at the Masters since 1997, produced a superb display of chipping and putting to return a 71.

Augusta National has been stretched to 7,445 yards since last year's tournament, making it the second longest course in major championship history.

First round scores: