Mickelson dropped only one shot in his opening round on the Monterey Shore AT & T Pebble Beach Pro-Am first class-7 B Gay (USA), S Langley (USA); -6 P Mickelson (US), M Every (US), S Kim (Kor), C Gribble (USA), J Day (Aus), K Kisner (USA) Other selected: -5 J Spieth (USA), D Johnson (U.S); -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
Five-time main champion Phil Mickelson scored a six-younger than 65 to share second place after the opening round of AT & T Pebble Beach Pro-Am in California.
The 48-year-old world number 29 made five birdies in eighth place on the Monterey Peninsula Shore course.
Jason Day also shot a 65 off at Monterey but world number 155 Brian Gay and 285-ranked Scott Langley shot 64-times.
Northern Irishman Graeme McDowell is four years after defeating the last hole in Pebble Beach.
Mickelson, who was second on Adam Long's Desert Classic last month but missed the cut in 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.
The Englishman Tommy Fleetwood, the world number 14, ran a triple bogey seven on the 13th and route to a 73 in Monterey.
Compatible Paul Casey birdied the last two lessons at Pebble Beach to return a round of three laps.
The players each play at Pebble Beach, Monterey and Spyglass Hill during the first three days before the final round takes place at Pebble Beach on Sunday.
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