World number five Adam Scott has begun the defence of his Houston Open title in style, breaking the course record to hold a share of the lead at the end of the opening round. Scott fought off the effects of virus to equal a course-record 63, previously established by Johnson Wagner and Bubba Watson last year. Wagner then went out and matched Scott&aposs score. Charlie Hoffman was two strokes behind, while Steve Stricker was three strokes off the lead. Scott&aposs round opened with a 55-foot birdie putt. He has now has played 54 holes without a bogey at this event. With a blemish free scorecard, Scott credited his improved putting game to his confidence around the course. “I just feel really comfortable on this golf course,” said Scott. “A lot of the shots really fit my eye. I feel like I know where to hit it. A few pins were in tough positions, but I picked a target and managed to stick to it. The more birdies I made, the confidence came and the swings became better. And by the end of it, I was playing great.” Scott hit 17 greens in regulation and needed just 28 putts but what made the round all the more remarkable was that he played with a fever and swollen glands. “I was just about conserving energy and thought about hitting the fairway and hitting the green and not having to work too hard. Fortunately, that&aposs kind of how today went. I need to keep going that way. It would be nice for the week.” Johnson&aposs round included an eagle on the eighth, where his approach shot from 262 yards came to a rest a foot from the pin. Phil Mickelson, the highest ranked player in the field, shot an even-par 72, while Ireland&aposs Padraig Harrington was one-under. Jose Maria Olazabal and Jesper Parnevik both finished at three-under, while Australian Geoff Ogilvy is well in contention after a five-under 67. Compatriot Steve Elkington matched Ogilvy&aposs 67, while Stuart Appleby, Mark Hensby and Rod Pampling are in touch after opening rounds of 70.