Woods will be looking for a fourth consecutive Buick title this week. The world No. 1 has won this event five times, including the last three tournaments.
This tournament is also Tiger's first appearance on the 2008 PGA Tour. In his 11 season-opening events, Woods has won five times and has never finished out of the top 10.
Mickelson is back in the field after three days of rest and treatment for a lung condition. The world No. 2 will be making his 18th consecutive appearance in the event.
This tournament holds special significance for Mickelson - he won his first PGA Tour title at the Buick Invitational in 1993. Mickelson had not played since winning the HSBC Champions tournament in China in November.
Eleven of the world's top 30 players are entered - including No. 4 Jim Furyk, South Korea's K-J Choi and Vijay Singh of Fiji. The tournament is being played on the par 72 Torrey Pines North course, which measures 6,286 meters. This week's winner will take home $936,000.
Some information for this report was provided by AFP, AP.