Two small objects caught manager Dave Martinez’s eye as Seth Romero entered his office on Thursday morning at Citi Field. Martinez had big news for the Nationals' No. 11 prospect, but not before getting something out of the way.

“I told him, ‘Hey, first and foremost, the earrings got to go,’” Martinez recounted. “‘And secondly, you’re going to pitch for us.’ You could see it in his face. He was elated.”

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Said Romero with a smile, “I didn’t even realize I still had them in.”

With the jewelry out, the lefty was in the Nationals' game plan for their series finale against the Mets. The 2017 first-round pick wasn't projected to make his Major League debut until next season, but when the Nationals’ bullpen was hit by injuries to its left-handers, though, his first big league appearance was fast-tracked to Thursday. He had been traveling with the team as a member of the taxi squad, and his contract was selected after lefties Sean Doolittle and Sam Freeman were placed on the IL.

Romero, 24, pitched 1 2/3 frames in relief of Austin Voth in the Nats’ 8-2 loss. He struck out four, walked three and allowed four runs off three hits. He began his debut by striking out Billy Hamilton, but his afternoon was marred when he allowed a two-out, 0-2 grand slam to Tomás Nido in the fifth.

“I wanted to get the changeup down like I did the first one I threw to him,” Romero said. “But I kind of just got under it, pushed it up there, gave him a good pitch to hit.”

Romero jumped from the Class A Hagerstown Suns to the Major Leagues, and his debut came nearly two years to the day since he last pitched in a game. He underwent Tommy John surgery in ‘18 and hadn’t made an appearance since Aug. 16 of that year.

“We watched him down in [Fredericksburg, Va., at the alternate training site], and he was a guy that was throwing strikes,” Martinez said. “That’s important here. He was throwing a lot of strikes, he’s always in the strike zone. He’s got a lot of swing-and-miss stuff, and we need a left-handed pitcher. Right now, he’s the only lefty we’ve got with Doo going down. We thought it’d be the perfect opportunity to get him up here and see what he can do.”

Romero has been lauded for his changeup, but on Thursday, of his 43 pitches, 21 were fastballs (which maxed out at 93 mph), 15 were sliders and just seven were changeups. Twenty-four pitches went for strikes.

“His stuff plays. I like it,” Martinez said. “Heartbeat was going 1,000 miles an hour, but he's going to be OK.”

There is an opportunity for Romero to contribute to an injury-hampered bullpen this season. After getting the feeling of being “100 percent nervous” while getting his first pitches out of the way, he is looking forward to the next call.

“Honestly, I don’t even really think that I’ve processed it yet,” Romero said. “But I can’t wait to get back out there on the mound again for whenever they need me, and I’m excited.”