Nick Taylor started strongly with an eagle and quietly toiled away to finish the first day at the three-course AT&T Pebble Beach Pro-Am atop the leaderboard with an eight-under 63.
Celebrities including former NFL quarterbacks Peyton and Eli Manning attracted attention at the tournament’s Spyglass Hill course, which suited the quiet Canadian who started on the back nine at Monterey Peninsula Country Club and closed the day with a pair of birdies.
Taylor has a two-shot lead over Americans Patrick Cantlay, who played at Spyglass, and the Pebble Beach-playing Chase Seiffert, who each had a six-under 66.
Defending champion Phil Mickelson was strong off the tee at Spyglass, tying for 12th with a four-under 68.
Graeme McDowell was the best of the Irish players, finishing tied 44th with a two-under 70 just days after he won the Saudi International.
Playing at Spyglass and starting from the 10th, McDowell opened with a bogey and reached the turn on level par after two birdies on 14 and 15 were quickly followed by another dropped shot on 16.
His back nine began with another bogey, on the par five first hole, but he finishes strongly - birdies on the second, sixth and seventh seeing him sign for a 70.
Pádraig Harrington also started his week with a 70 at Monterey Peninsula, while Seamus Power is level par after a 72 at Pebble Beach.
Collated first round scores in the USPGA Tour AT&T Pebble Beach Pro-Am (USA unless stated, par 71)
Pebble Beach GC
66 Chase Seiffert
67 Harold Varner III, Robert Streb
68 Matt Jones (Aus), Matthew NeSmith
69 Wes Roach, Henrik Norlander (Swe), Stewart Cink, Tim Wilkinson (Nzl), Alex Cejka (Ger)
70 Peter Malnati, Lucas Glover, Ryan Armour, Matt Every, Matt Kuchar
71 Kristoffer Ventura (Nor), J.B. Holmes, Xinjun Zhang (Chn), Vincent Whaley, Tyler McCumber, Bol Hoag, Matthew Fitzpatrick (Eng)
72 Ben Martin, Maverick McNealy, Chris Kirk, Vaughn Taylor, Ted Potter, Jr., Zack Sucher, David Lingmerth (Swe), Seamus Power (Irl)
73 Nick Watney, Brian Stuard, Scott Stallings, Brandon Hagy, Nelson Lauta Ledesma (Arg), Michael Thompson, Kiradech Aphibarnrat (Tha), Michael Gellerman, Tyler Duncan, Anirban Lahiri (Ind)
74 J.J. Henry, Hank Lebioda, Robert Garrigus, Mark Hubbard, Roberto Castro, Mackenzie Hughes (Can)
75 Bol Van Pelt, Scott Ger Borba
76 Andrew Landry, Dominic Bozzelli
77 Scott Brown
84 David Duval
Spyglass Hill GC
66 Patrick Cantlay
67 Max Homa, Charley Hoffman, Lanto Griffin
68 Phil Mickelson, Wyndham Clark, Kevin Chappell
69 Dustin Johnson, Kurt Kitayama, Brandon Wu, Zac Blair, Troy Merritt, Kevin Streelman
70 Daniel Berger, Graeme McDowell (NIrl), Viktor Hovland (Nor), Jordan Spieth
71 Pat Perez, John Senden (Aus), Paul Casey (Eng), Chesson Hadley
72 Sebastian Cappelen (Den), Brian Gay, Luke Donald (Eng), Michael Gligic (Can), Kevin Kisner
73 Jason Dufner, Branden Grace (Rsa), Nate Lashley, Doc Redman, Peter Uihlein, Ben Taylor (Eng), Sean O’Hair, Jimmy Walker, Ryan Brehm, Martin Trainer, Brandt Snedeker
74 Steve Stricker, Chad Campbell, Jim Furyk, Adam Long, Adam Hadwin (Can), Russell Knox (Sco)
75 Kevin Na, Arjun Atwal (Ind), David Hearn (Can), Smylie Kaufman
76 Chris Stroud, Patrick Rodgers
77 D.A. Points, Si Woo Kim (Kor)
78 Austin Cook
Monterey Peninsula Country Club
63 Nick Taylor (Can)
66 Richy Werenski, Ricky Barnes, Harry Higgs
67 Jason Day (Aus), Justin Suh, Charl Schwartzel (Rsa), Greg Chalmers (Aus), Jim Herman, Jonathan Byrd, Chez Reavie
68 Adam Schenk, Beau Hossler, Aaron Wise, Scott Piercy, Doug Ghim, Aaron Baddeley (Aus), George McNeill, Rob Oppenheim, Scott Harrington
69 Alex Noren (Swe), Christopher Baker, Keith Mitchell, J.J. Spaun, Tom Hoge
70 Rafael Cabrera-Bello (Spa), Brice Garnett, Johnson Wagner, Padraig Harrington (Irl), Josh Teater
71 Cameron Champ, Cameron Davis (Aus), Joel Dahmen, Bill Haas, James Hahn, Joseph Bramlett, D.J. Trahan, Cameron Tringale
73 Rod Pampling (Aus), Fabian Gomez (Arg), Patrick Martin, Mark Anderson
74 Hunter Mahan, Kramer Hickok, Sung Kang (Kor), Rhein Gibson (Aus), Isaiah Salinda, Kyung Ju Choi (Kor)
76 Satoshi Kodaira (Jpn)
77 Kevin Stadler, Sam Saunders
78 Tim Herron