Phil Mickelson dispelled any lingering doubts about his health ahead of the Masters when he carded an impressive four-under-par 68 in the opening round of the Houston Open.

A week before the start of the year's first major, Mickelson recorded four birdies during a bogey-free round to end the day three strokes behind American leaders Bill Haas and Charley Hoffman in ideal scoring conditions at the Golf Club of Houston.

Mickelson, a perennial contender at Augusta National, withdrew from last week's Texas Open during the third round with a pulled abdominal muscle.

It was merely a precautionary decision, because the three-times Masters champion was at Augusta National early this week for a practice round on his way to Houston.

"I felt great today," Mickelson told Golf Channel. "I didn't feel any pain or discomfort and didn't even think about it. I'm surprised, because I was worried when it happened about the Masters but it healed a lot quicker (than expected)."

Mickelson ended the day equal 18th, with Haas and Hoffman shooting 65 to head a group of five players, including Matt Kuchar, by one stroke.

Source: Reuters