Holder Adam Scott of Australia and American Johnson Wagner fired course records of nine-under-par 63 on Thursday to share the lead after the first round of the Houston Open.

Scott birdied six of his first nine holes after starting at the 10th and added three more birdies in a bogey-free round at Redstone Golf Club's Tournament Course.

The fifth-ranked Scott told reporters his sizzling round came despite feeling sick.

"I've been feeling lousy all this week," said Scott. "I'm going to get some antibiotics once I leave here."

Scott, 27, said he perked up once he got to the course.

"I just feel really comfortable on this golf course. A lot of the shots really fit my eye," the Australian said.

"I feel like I know where to hit it.

"I was just about conserving energy and thought about hitting the fairway and hitting the green and not having to work too hard," added Scott, who hit 17 of 18 greens.

The 28-year-old Wagner looks to have found form again at Redstone, where he had shared the course record with Bubba Watson after shooting 64 last year.

He surged at the finish of his afternoon round with a tap-in eagle at the par-five eighth and a birdie at the ninth to reclaim a share of the course mark by matching Scott.

Wagner came into the tournament ranked 181st in scoring average this year after missing six cuts.

"I've been struggling a little lately but I've been working hard," said Wagner, looking for his first U.S. Tour win.

American Charley Hoffman, who has missed his last seven cuts, was alone in third place at 65, two strokes behind the co-leaders.

A shot further back was world number four Steve Stricker, who posted a 66, one better that 2006 U.S. Open champion Geoff Ogilvy, his fellow-Australian Steve Elkington and Americans Briny Baird and Dean Wilson.

John Daly failed to take advantage of good scoring conditions in the morning, posting a six-over 78 on a layout set up to mimic features of Augusta National, site of next week's first grand slam of the year, the Masters.

World number two Phil Mickelson came to his last hole at two under par, but dumped his tee shot into the water and finished with a double-bogey for even-par 72.

Among other notables, twice Masters champion Jose Maria Olazabal of Spain, Sweden's Jesper Parnevik and Davis Love III were all in a large group at three-under 69.

Love must win the tournament to join next week's Masters field and continue his streak of playing in 70 successive majors dating back to the 1990 British Open. 

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