Sam Saunders, the grandson of late golfing legend Arnold Palmer, holds a two-shot lead after the first round of the Genesis Open at the Riviera Country Club in California.
The 29-year-old - participating in the tournament after being invited by a sponsor - carded a bogey-free round of 64 to lead the way on a day which saw play delayed due to fog and a number of competitors unable to complete their first round.
A five-way tie for second includes Dustin Johnson, who is aiming to end the week as world number one, while Phil Mickelson and Ireland's Padraig Harrington are a stroke further back.
Adam Scott and Luke Donald carded a round of 68, with England's Justin Rose and Paul Casey both on two-under.
Play resumes later today when the likes of current world number one Jason Day will complete their opening round.