Paul Casey and Webb Simpson have finished the opening day of the Sony Open with a tie of the lead on eight-under-par in Hawaii.

Casey, playing in the event at Waialae for the first time in a decade, carded nine birdies in an impressive start for the 37-year-old, who missed out on equalling the competitive course record by a stroke.

The Englishman was joined at the top of the leaderboard by Simpson, who was playing in his first event since taking the belly putter out of his bag.

Simpson was just one-under at the halfway stage of his round, before a superb run of holes saw him record a 62.

Camilo Villegas and Robert Streb are a shot further back, while Rory Sabbatini is currently on six-under.

Jason Day and Matt Kuchar remain in contention after a low-scoring day, with both players sitting just three strokes behind the leaders.