|AT&T Pebble Beach Pro-Am first-round leaderboard|
|-7 B Gay (US), S Langley (US); -6 P Mickelson (US), M Every (US), S Kim (Kor), C Gribble (US), J Day (Aus), K Kisner (US)|
|Selected others: -5 J Spieth (US), D Johnson (US); -4 M Laird (Sco), G McDowell (NI); -3 P Reed (US), R Knox (Sco), P Casey (Eng); -1 S Lowry (Ire), M Fitzpatrick (Eng); level B Davis (Eng); +2 T Fleetwood (Eng)|
Five-time major champion Phil Mickelson carded a six-under 65 to share second place after the opening round of the AT&T Pebble Beach Pro-Am in California.
The 48-year-old world number 29 made five birdies on the back nine at the Monterey Peninsula Shore course.
Jason Day also fired a 65 at Monterey but world number 155 Brian Gay and 285th-ranked Scott Langley shot 64s.
Northern Irishman Graeme McDowell is four under after bogeying the final hole at Pebble Beach.
Mickelson, who was runner-up to Adam Long at last month’s Desert Classic but missed the cut at the Phoenix Open last week, hit all 13 fairways for the first time in a PGA Tour round since the Farmers Insurance Open in 1998.
Englishman Tommy Fleetwood, the world number 14, ran up a triple bogey seven at the 13th en route to a 73 at Monterey.
Compatriot Paul Casey birdied the final two holes at Pebble Beach to return a three under opening round.
The players each play at Pebble Beach, Monterey and Spyglass Hill over the first three days before the final round takes place at Pebble Beach on Sunday.