Dodgers’ 8-4 loss to Padres exposes weaknesses

SAN DIEGO — If the first three games provided reasons why the Dodgers could make a run at the playoffs, their 8-4 defeat to the San Diego Padres on Sunday at Petco Park reintroduced the unsettling possibility that this season might be similar to last.

Except for Clayton Kershaw and Chad Billingsley, their rotation is showing signs that it could be a severe handicap.

A day after Chris Capuano pitched only 42/3 innings against what is arguably the worst lineup in baseball, No. 4 starter Aaron Harang sent the Dodgers crashing to their first defeat by lasting a mere 41/3.

“I was pitching kind of tight; it was like I was tense or something,” said Harang, who gave up four runs — three earned — seven hits and five walks.

Harang, who pitched for the Padres last season, said he didn’t know whether he was nervous because he was facing his former team or because he was pitching for the Dodgers for the first time.

Manager Don Mattingly said he was certain Harang and Capuano would pitch better but acknowledged, “We’re going to have to get more than that.”

And more than 100 miles north, in Rancho Cucamonga, No. 3 starter Ted Lilly was hit hard by the Angels’ Class-A affiliate in a rehabilitation appearance.

Lilly, who started the season on the disabled list because his throwing program was derailed by a stiff neck, served up two home runs. He was charged with seven runs — six earned — and eight hits in six innings.

The left-hander is scheduled to make his season debut April 14 against the Padres at Dodger Stadium.

Capuano and Harang’s abbreviated starts over the last two days have exposed some frailties of the promising but inexperienced bullpen.

The Dodgers have only one left-handed reliever in former first-round pick Scott Elbert, and he isn’t pitching well.

Elbert threw a run-scoring wild pitch Saturday that helped the Dodgers squander a five-run lead. On Sunday, he served up a grand slam to Chase Headley that put the game out of reach.

Offensively, there are also disconcerting signals.

The Dodgers made Padres starter Clayton Richard look like Clayton Kershaw, as the left-hander held them to two runs and two hits in seven innings.

Matt Kemp and Andre Ethier each hit a two-run home run Sunday and each drove in eight runs over the four-game series. But third baseman Juan Uribe and first baseman James Loney are slumping as much as Kemp and Ethier are flourishing.

Uribe collected the Dodgers’ first hit against Richard, in the fifth inning, but the single to right field was his only hit in the series in 12 at-bats. Uribe, who batted .204 in an injury-shortened 2011 season, has struck out four times.

Loney, who nearly hit his way out of town last season, was 0 for 12 with three strikeouts in the series.

Loney spent the spring focusing more on timing and less on mechanics. He doesn’t think he has moved backward.

“I felt pretty good,” he said.

Whatever the shortcomings the Dodgers exhibited in this season-opening series, Kemp went into the day off Monday encouraged .

“We did a great job this series,” Kemp said. “Our objective is to try to win every series and that’s what we accomplished on this first road trip. We won a game in extra innings. We tried to fight back in this game. The character of our team is strong. We never give up.”

The Dodgers resume play Tuesday when they play host to the Pittsburgh Pirates in their home opener.

dylan.hernandez@latimes.com