Dodgers reliever Hong-Chih Kuo struggles mightily in return

It wasn’t the return Hong-Chih Kuo or the Dodgers had in mind.

After being reinstated from the 15-day disabled list Sunday morning, the hard-throwing reliever started the ninth inning of Sunday’s game, with the San Diego Padres leading the Dodgers, 3-0.

But the left-hander never got on track. After 25 pitches, Kuo was charged with four earned runs, two hits, one walk and one hit batter in one-third of an inning, against the worst-hitting team in baseball. The bases were loaded with one out when Dodgers Manager Don Mattlingly lifted him.

“I’m not perfect,” said Kuo, an all-star last year who said before the game that it was good to be back after a lower back strain put him on the disabled list, and now he feels “100%.”

Asked whether his problems Sunday were more mechanical than physical, Kuo replied, “Everything, I guess. When you struggle, you can say anything’s wrong. But I’m [going] to go out there and battle and try to get better.”

Kuo is another option to finish games amid still-lingering doubts about the effectiveness of closer Jonathan Broxton, though Kuo’s showing could add doubts of its own. Regardless, Mattingly said, “we wouldn’t have activated [Kuo] if he didn’t feel he was ready and we didn’t feel like he was ready to go.”

Jansen’s journey

To make room for Kuo, the Dodgers sent Kenley Jansen down to double-A Chattanooga. But the 23-year-old reliever vowed to be back later this season.

“I’m very disappointed,” Jansen said, but “I’m going down there and work” hard to return to the big leagues.

Jansen, a native of Curacao, dazzled as a rookie in the second half of last season after being called up from Chattanooga, skipping past triple-A Albuquerque. He had four saves, a 0.67 earned-run average and 41 strikeouts over 27 innings.

But the 6-foot-5 right-hander struggled in the first month of this season. In 131/3 innings, he allowed 11 runs, 13 hits and had a 7.43 ERA.

Mattingly said Jansen had been “pitching good” but “there’s still room for improvement.”

Jansen needs “a little bit more of a consistent secondary pitch, to be able to use his change more or use the breaking ball enough to keep [batters] off. He’s pretty fastball-dominant right now.”

“It’s an opportunity for him to go down and basically work on all aspects of his game,” Mattingly said, “being able to hold runners [on base], working on his move [to first base], all the little things that you don’t really notice besides the strikeouts.

“At some point he’s going to be back here. We really look at Kenley as a big part of the future.”

Cormier’s role

Mattingly also was asked about right-handed reliever Lance Cormier, who arrived Sunday having made only five appearances this season, the last April 22, and who’s been roughed up for 11 runs (nine earned) in eight innings.

Cormier’s role currently is “to protect everybody else” in the bullpen, especially in lopsided games, so the Dodgers don’t have to use Jonathan Broxton or Kuo, Mattingly said.

So it was Sunday, when Cormier was called in to mop up in the ninth inning with the Padres ahead, 7-0.

james.peltz@latimes.com