But there was still an opportunity to gain a game on the Giants, who remain 4 1/2 up in the division, and the Cardinals, who are still 1 1/2 games up on both the Dodgers and Pirates in the Wild Card standings.
And it looked like at one point late in the game that was going to be the case. With the Dodgers trailing, 4-3, in the seventh, it appeared that Matt Kemp was going to put them ahead with a two-run homer to straightaway center.
But Cameron Maybin made a leaping catch at the wall and Kemp was left with nothing to show for his blast to the deepest part of Dodger Stadium as L.A. came up with another empty inning.
The Dodgers failed to score a run or register a hit for the final four innings against an inexperienced San Diego bullpen.
"It's a bunch of rookies trying to make a huge contributions to the cause," Padres manager Bud Black said. "That's great to see. And especially against a very good lineup over there."
Although it is a pleasant sight for Black, it is concerning for the Dodgers, who boast an experienced lineup of All-Stars in which the two-time All-Star Kemp is the youngest regular offensive player.
What makes the problem even worse for Mattingly is the overused bullpen he keeps having to use early and often. On Wednesday, he had to pull one of his hottest hitters, Luis Cruz, in a double-switch after the fifth because the offense was scuffling and he needed Shawn Tolleson to pitch a second inning.
The move backfired and Tolleson gave up what would be the game-winning RBI on a sacrifice fly in the seventh inning.
"Every series is must-win in September," Kemp said. "There are no excuses. We've got to play ever game like it's our last game. You never know what can happen."
After starter Aaron Harang threw 61 pitches in the first two innings -- he gave up three runs in the first -- any hopes to give the bullpen a rest went away quickly. Harang wound up settling down, but he was able to go only five innings.
The Dodgers wound up using four relievers -- Tolleson, Jamey Wright, Randy Choate and Brandon League -- in the loss.
"You want to get in through sixth into the seventh, maybe the eighth inning to try and give those guys a break, especially this point in the year," Harang said. "With that long first inning throwing a lot of pitches, that ultimately hurt me in going out there for a sixth inning."
The Dodgers scratched back into the game with runs in the second, third and fifth to tie the game, but they recorded three hits in each of those innings and came away with only one run each time.
"Our offense kind of chipped away and got back in the game," said Mattingly, whose team put together 10 hits -- all singles. "We weren't able to get over the hump."
While the Dodgers are playing for the division and not the Wild Card, they are closer to catching the Cardinals at this point than the Giants. And like San Francisco on Wednesday, St. Louis lost and gave Los Angeles an opportunity to pull within a half-game of the second Wild Card spot.
The two teams will face off in a four-game set at Dodger Stadium next week in one of many tough series ahead for L.A., which also faces the division-leading Nationals and Reds.
"We control our own destiny by going out there and winning," outfielder Shane Victorino said. "Now we get a chance to play against the team that is ahead of us. We've just got to stay focused. That helps that we play the teams we are chasing."
But before the Dodgers can worry about those series, they first have to travel to San Francisco. If the series shakes out like the last three, which were all sweeps, Los Angeles will either find itself on the heels of a playoff berth or gasping for air and a week's worth of games out.
"It's hard to explain what is going on with it," said Mattingly, who will also see the Giants for the final three games of the season. "I like the trend if we win the first game."