The Giants have scored just 10 runs in their first five games this season, while their opponents have recorded 21 runs.
"The important thing now is we got to put some runs on the board and start clicking offensively," manager Bruce Bochy said.
Saturday's loss gives the Dodgers seven consecutive wins at AT&T Park, a streak that started last Aug. 19 with a 14-7 Giants defeat.
Starting pitcher Russ Ortiz's new semicircle delivery looked like it was living up to the hype in the first two innings when he allowed just one hit, but the Dodgers looked more comfortable at the plate their second time through the lineup.
With two outs in the fourth, Ortiz allowed two singles, then walked Andre Ethier and Wilson Betemit, who was batting eighth, to load the bases and walk a run home, tying the score at 1.
Giants pitchers have walked the eighth batter four times in the five games they have played this season, with two of those walks resulting in runs.
Ortiz's performance continued to decline in the fifth when he allowed three hits, including a double from Jeff Kent that brought in two runs.
"You've got to give [the Dodgers] credit; they did a good job of laying off pitches," Ortiz said. "It's just a matter of time. You want to get off to a good start but that didn't happen, so I've just got to be patient."
Ortiz allowed seven hits and three runs and walked three in five innings for a decent first start. Ortiz, who played for the Giants in 2002, has not recorded a win since Aug. 29, 2005. Right-hander Derek Lowe used his sinker to hold the Giants to four hits and one run in seven innings.
Although the Giants lost, Todd Linden looked sharp in his first start of the season. The backup left fielder came up with two big catches, including a leap for a high fly almost to the wall in the sixth inning. Linden also singled in the fifth and was the benefactor of one of Lowe's two walks in the game.
After the game, Linden said it is important to keep perspective on how long the season is.
"There's no need to hit the panic button," Linden said. "I'm not as worried about the slow start. I'm worried that some guys are going to accept it or start to get discouraged."
Linden's defensive contributions were complemented by Rich Aurilia's offense. Aurilia went 2-for-4 and knocked in the Giants' only run of the game with a double to left-center field in the second inning.
After Aurilia's double, the Giants were not able to get a runner past first base.
"It's not the start we wanted," Bochy said, "but there's so much baseball left and we'll get going here offensively."