ARLINGTON — Left-hander Hyeon-Jong Yang was supposed to go to Round Rock on Monday to play in the Rangers’ alternate training site games against the Royals’ alternate site team.

Then the Rangers called Monday morning and told him to hold off before leaving. Then another call came a few hours later, telling the 14-year Korean baseball veteran that he was called up to the big league squad.

Yang made his MLB debut in a relief appearance Monday night, pitching 4 1/3 innings and giving up two runs in the Rangers’ 9-4 loss to the Angels at Globe Life Field.

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“The two runs that I had to concede was kind of a bummer for myself,” Yang said through an interpreter. “If I didn’t give any runs up when I was pitching, that might have given the team a chance to win back the game. So although everybody congratulated me and complimented me, I feel sorry for having given those up.”

Yang’s outing was the second-longest relief appearance by a Ranger in his Major League debut. Steve Wilson went 5 1/3 frames on Sept. 16, 1988, also against the Angels.

Manager Chris Woodward said he was pleasantly surprised with how effective Yang was in his debut.

“I didn’t really know what to expect, but he was impressive,” Woodward said. “[Catcher Jose Trevino] was coming back and just saying, ‘Man, this guy can execute everything.’ He made a mistake [a solo home run by José Iglesias], just didn’t get [the pitch] down, but other than that, they only hit a few balls hard off of him. It was really, really effective.”

Yang entered the game after starter Jordan Lyles only went 2 2/3 innings, giving up seven runs on 10 hits and three walks. Yang made quick work, getting Anthony Rendon to pop out on the infield to strand runners in scoring position.

“I wasn’t really nervous about it,” Yang said. “It was actually fun to play where our fans are in the ballpark. I didn’t really think of the other opponents, but I was trying to throw out what I have, and what I can offer the team.”

Yang was signed to a Minor League deal this offseason and has spent the early part of the regular season on the taxi squad or at the alternate training site before the callup. The Rangers’ bullpen was short Monday based on the amount of innings thrown during the weekend series at Chicago, and Yang gave the club length out of the bullpen.

Yang said he came over from Korea to challenge himself and he was focused on delivering a good first impression on the Major League stage. And though he gave up two runs, he enjoyed the moment on the mound.

“There’s a reason that the Major League mound is called the dream ballpark,” Yang said. “I want to show who I am to the people in the United States. I’ve been trying really hard to be on the mound since the preseason, so I don’t want this to be just a one-time thing.”

The Rangers’ losing streak extended to four games, despite a loud start on Nate Lowe’s three-run homer in the first inning off two-way star Shohei Ohtani — projected at 428 feet by Statcast.

The offense went virtually silent after a four-run first inning. Ohtani pitched three straight perfect innings before finally giving up a single to Isiah Kiner-Falefa in the fifth. The Rangers scattered singles throughout the rest of the game but weren’t able to get another run across.