Beyond three star players, Dodgers head into the unknown

SAN DIEGO — Of the countless questions the Dodgers faced heading into spring training, the most important pertained to outfielder Andre Ethier.

Specifically, would he recover from the knee injury that drained him of his power last season?

The 18 spring-training games Ethier played in Arizona answered the question.

“A month of running on it, swinging on it, staying on my legs, up to this point I haven’t had an issue,” Ethier said.

He batted .396 with three home runs and 16 runs batted in. Of his 19 hits, 15 were for extra bases. Most important, Ethier performed free of pain.

There are no guarantees in baseball, but the Dodgers head into their season opener Thursday in San Diego reasonably certain that they have three All-Star-caliber players — Ethier, center fielder Matt Kemp and pitcher Clayton Kershaw.

Beyond that, well …

When the Dodgers broke camp in Arizona, Manager Don Mattingly offered a candid assessment of his club, acknowledging numerous questions remain.

“Offensively, we have unknowns,” Mattingly said.

Mattingly pointed to first baseman James Loney and third baseman Juan Uribe.

“Is James going to keep being James?” Mattingly said. “Is Juan going to bounce back to give us production he’s had historically?”

Loney appeared to be hitting his way out of Los Angeles last season until he turned into Babe Ruth in mid-August. Uribe’s first season of a three-year, $21-million deal was a complete failure; the hefty infielder was limited to 77 games and batted only .204.

Outfielder Juan Rivera is one of the batting order’s “Big Three,” Kershaw said, but his track record is that of a streaky hitter.

Acquired at almost no cost from the Toronto Blue Jays in August, Rivera protected Kemp during his late-season run at the triple crown. Rivera was re-signed by the Dodgers for $4.5 million.

Rivera will bat fifth on most days; he will swap places with Ethier and hit cleanup behind Kemp on days the Dodgers face a left-hander.

Rivera said he is up to the task.

“When you have confidence at the plate, it doesn’t matter where you hit — third, fourth or fifth,” he said. “That’s what happened last year. I had a lot of confidence. I told myself, ‘I can hit behind Kemp.’ I think I did well hitting behind him. Yes, you feel a lot of responsibility. But when you have confidence, you don’t think about it much.”

The player most capable of transforming the Dodgers’ offense is at the top of the lineup: second-year shortstop Dee Gordon.

Called “the most exciting player in baseball” by Kemp, Gordon has game-changing speed. But for him to make a run at the stolen base title, he will have to first get on base — something he hasn’t done over an entire major league season.

He stole 24 bases and hit .304 in 56 games last season — .232 in his first major league call-up and .345 in his second.

How players such as Loney, Uribe, Rivera and Gordon perform probably will determine whether the Dodgers have enough offense.

Even with Kemp delivering arguably the greatest offensive year in franchise history, the Dodgers won only 82 games last season. Mattingly warned that the team can’t be overly reliant on Kemp, who fell a home run short of becoming the fifth player in history to hit 40 home runs and steal 40 bases in the same season.

“To say Matt’s going to have that kind of year again is reaching a little bit,” Mattingly said. “To say Matt has to go 40-40 or 50-50 is expecting almost too much. You have to be realistic.”

The questions aren’t limited to the offense.

The back end of the bullpen is widely considered a strength, but Mattingly thinks second-year closer Javy Guerra and setup man Kenley Jansen have something to prove.

“They reacted well last year, but we were 10, 12 games back,” Mattingly said. “Those games, they were meaningful to us, but in a sense we were 12 back, so the pressure on those guys was different.”

Guerra converted 21 of 23 save opportunities. Jansen averaged a major league record 16.1 strikeouts per nine innings.

The bullpen has only one left-hander, Scott Elbert, and he is also short on experience. Of his 592/3 career innings, 331/3 came last season.

How much the Dodgers rely on their young bullpen will depend on the starters.

Kershaw, the reigning Cy Young Award winner, significantly tilts the odds in their favor once every five days.

The other four days?

Chad Billingsley, No. 2 in the starting rotation, is only two games over .500 in the last three seasons. He was encouraged by an adjustment he made in his mechanics and the progress he made on his changeup, but posted an unsightly 5.91 earned-run average in spring training.

Soft-tossing Ted Lilly was usually either spectacular or spectacularly awful last season as evidenced by the team-high 28 home runs he served up. He will miss his first start because a stiff neck threw off his spring throwing program.

Newcomers Aaron Harang and Chris Capuano have histories of medical problems and erratic performances.

Harang last pitched 200 innings in 2007. He was 14-7 with a 3.64 ERA in 28 starts with San Diego last season but had a 4.70 ERA away from pitcher-friendly Petco Park.

Capuano made 31 starts for the New York Mets last season but sat out the 2008 and 2009 seasons because of a reconstructive elbow operation. A left-handed finesse pitcher, he had a 4.55 ERA and served up 27 home runs last season.

But at least Mattingly knows whom he’ll play. Last year, the Dodgers started the season with five players on the disabled list, including their starting third baseman and left fielder.

This season, Lilly is the only key player on the DL and he is expected back soon.

dylan.hernandez@latimes.com