Paul Casey earned a three-stroke lead over Phil Mickelson after the third round of the AT&T Pebble Beach Pro-Am.
Casey started the day in a five-way tie for first place, but the Englishman ended Saturday atop the leaderboard following his five-under-par 67.
The two-time PGA Tour winner and 13-time European Tour champion moved to 15 under through 54 holes following six birdies throughout the round.
While Mickelson would have liked to cut into the lead a little bit more after his two-under-par 70 on moving day, the American star still managed to hit a lifetime mark which made the day memorable.
By making the cut early on Saturday, the five-time major champion has now made 500 cuts in his storied career.
That makes Mickelson's up-and-down day which featured four bogeys, four birdies and an eagle much more palatable.
Scott Piercy (69) and Lucas Glover (70) are four shots back of Casey at 11 under for the tournament, while Brian Gay (69) and Matt Every (69) are a stroke further back.
Elsewhere on the course, Jordan Spieth's double-bogey at the 18th dropped him from what would have been a tie for seventh place to a tie for 18th at seven under.
Seeking his first victory since 2017, former world number one Spieth – who returned on Saturday morning to complete his second round after rain and wind hit the event on Friday – posted a two-over-par 74 in the penultimate round.
Australian Jason Day is in that tie for seventh at nine under following his 72, while Dustin Johnson's 73 saw him drop 12 shots off the pace heading into Sunday.