Arizona-based Casey, who has quit the European Tour to focus on playing in the United States, made his move with five consecutive birdies around the turn.

He and Simpson are a stroke ahead of Colombian Camilo Villegas at Waialae Country Club in Honolulu, with half the field yet to complete their round.

Simpson, the 2012 U.S. Open champion, also had five straight birdies on almost the identical stretch of holes as he charged home in 28 strokes on his inward half (the front nine).

Simpson wielded a regular-length putter with aplomb after recently abandoning the belly putter ahead of the new regulation banning players from anchoring the club from next year.

Simpson, whose long game was also on song after a pre-tournament session with instructor Butch Harmon, rolled in four birdie putts from outside 15 feet on his way home.

Latest News from Sports News Desk