FIRST ROUND LEADERBOARD:
-8 S Piercy (US) -7 B Crane (US), C Tidland (Us), R Imada (Jpn), M Every (US) -6 T Pernice Jr (US)
Selected others: -2 P Mickelson (US), L Donald (Eng), E Els (SA) -1 J Rose (Eng), G Owen (Eng), M Laird (Sco)
Mickelson will play the easier North course in his second round
Phil Mickelson got his 2010 campaign under way with a cautious two-under-par 70 in his opening round at the Farmers Insurance Open in San Diego.
The world number two played the longer Torrey Pines South course, finishing six shots behind leader Scott Piercy.
"I was a little more cautious today because I didn't want to make too many big mistakes," said Mickelson.
Luke Donald carded 70 on South, while Justin Rose, Greg Owen and Scotland's Martin Laird all shot 71 on the North.
Former Open and USPGA champion John Daly had a day to forget on the Pacific coast.
Daly posted an opening seven-over-par 79 on the South, which included four bogeys and a triple-bogey seven at the 14th.
For American Mickelson, who finished 2009 with back-to-back victories at the Tour Championship and WGC HSBC Champions, Daly's was exactly the kind of round he was looking to avoid.
"Jack Nicklaus used to talk about that in majors, that he wanted to try to progress as the week went along, and I didn't want to try to come out and win the tournament on Thursday because it's just not possible," said Mickelson.
"I wanted to try to build into it, so I'm hoping I play better tomorrow and shoot a low score on the North, good enough to get myself in contention for the weekend."
Mickelson carded five birdies and three bogeys on the 7,569-yard South course, while leader Piercy's 64 came on on the easier 6,874-yard North.