SEOUL -- When the Dodgers signed Yoshinobu Yamamoto to a record 12-year, $325 million deal this winter, the organization made it clear that they believed the Japanese right-hander was worth every penny despite not having thrown a pitch in the Majors.

Most scouts around the league believed the same. It’s why there were more than a handful of organizations involved in Yamamoto’s free-agent process. But with that massive deal, there were also some skeptics.

Whether Yamamoto performs to his contract or not will be determined over the next decade, not just one start. But Yamamoto’s first taste of the Majors ended in disappointment as the right-hander got through just one inning, allowing five runs on four hits and one walk, with one hit-by-pitch in the Dodgers’ 15-11 loss to the Padres on Thursday at Gocheok Sky Dome. He needed 43 pitches to get through the frame.

“I feel regret that I just couldn’t keep the team in the game from the get-go,” Yamamoto said through interpreter Yoshihiro Sonado. “So I do feel a responsibility for it. Like I said, I just have to get ready for the next outing.”

Yamamoto became the first Dodgers starter since at least 1901 to allow five runs in his Major League debut in an outing that lasted one or fewer innings. It's also the shortest outing by a Dodgers starter making his MLB debut since Ralph Mauriello in 1958.

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Yamamoto’s start got off on the wrong foot from the jump. The first pitch of his career was hit into left field by Xander Bogaerts for a single that had an exit velocity of 105.4 mph. Two batters later, Jake Cronenworth hit a two-run triple off Yamamoto to open the scoring. Luis Campusano and Tyler Wade had two-out RBI hits in the frame, giving the Padres a 5-0 lead in the first.

“I wasn’t able to execute a pitch from the stretch,” Yamamoto said. “I know how to fix it, and I’m going to talk to my pitching coaches Mark [Prior] and Connor [McGuiness] and fix it for my next outing.”

When Yamamoto came over from the Nippon Professional Baseball league in Japan, scouts and executives around the league raved about his command. It’s what propelled him to becoming the best pitcher in the league, winning the pitching Triple Crown each of the last three seasons.

That command, however, was lacking throughout the spring, and Yamamoto finished Cactus League play with an 8.38 ERA in three starts. The bad Spring Training results were pushed aside by the Dodgers, citing some tinkering and adjustments to the Major League ball as the reason for some of the struggles.

But on Thursday, the command again wasn’t there for Yamamoto, who only threw 23 strikes out of his 43 pitches. The Padres recorded hits off Yamamoto’s four-seamer, cutter and signature splitter. The Japanese right-hander recorded five whiffs on 18 swings.

“When you’re a command guy, which he’s been his entire career, his life, and you misfire and get behind in counts and hit batters, that’s just not who he is,” manager Dave Roberts said. “So we just got to get back to refining the delivery, tightening up the command, and he’ll be fine. But it’s just one of those things that, he’s [a] ... guy that you know he’ll bounce back from this.”

The Dodgers insisted before the game that they weren’t going to overreact to the first result of Yamamoto’s career. Still, it wasn’t the start anybody envisioned for the Dodgers’ new $325 million man.

"I mean, I've definitely seen sharper from him,” said Dodgers catcher Will Smith, who recorded four hits and drove in a pair. “I thought he competed. It was his debut. Obviously would have liked it to have been a little better. But we'll learn, we'll keep going and I expect a lot from him this year."

Behind Yamamoto, the rest of the Dodgers’ pitching staff struggled. Michael Grove allowed four runs (three earned) over two innings. Kyle Hurt, Alex Vesia and J.P. Feyereisen all allowed at least one run in their respective outings. The Dodgers’ defense was also shaky on Thursday, particularly Max Muncy, who committed two errors at third. Mookie Betts was a bright spot on offense, tallying four hits and six RBIs in a banner day for the newly minted Dodgers shortstop.

Los Angeles was hoping to win a pair of games against the Padres in Seoul before returning home. Instead, they head back to the United States with a series split and some question marks.

“On the pitching side, it just wasn’t very good,” Roberts said. “Across the board, we just didn’t execute. [10] walks in there [in two games]. And defensively, we weren’t good either. You’re just not going to prevent runs that way.”