Kelvin Herrera walked into the home clubhouse at Nationals Park at approximately 4 p.m. on Tuesday, about 20½ hours after he learned he would be leaving the only major league club he’d ever called home, still lugging a Royals blue duffel bag. Coordinator of Baseball Operations John Wulf walked him in and pointed him to his locker, the first one to his left, a free locker down from that of former Royals teammate Tim Collins.

Herrera settled into his chair and chatted with Collins as clubhouse manager Mike Wallace helped him figure out this and that. Could he borrow someone’s spikes tonight? Royals colors wouldn’t work, and they hadn’t had time to get Nationals-colored cleats sent over yet. Eventually another former Royals teammate, Ryan Madson, wandered over to greet him, too.

“It’s like when you move to a neighborhood, and in the neighborhood there are two neighbors that you’ve lived near before,” Herrera said later in Spanish. “Obviously, we get along really well, and that makes me feel really good.”

The Nationals had waited for Herrera to arrive to announce the moves that would create a roster spot for him, and while Herrera sat at his locker, reliever Wander Suero got the call to the manager’s office. Washington optioned Suero to Class AAA Syracuse. The club also placed Matt Adams on the 10-day disabled list after X-rays revealed a broken finger. Then, shortly after he’d pulled on a Nationals undershirt for the first time, Herrera headed in to talk to his new manager, who had a quick chat with the former Royals closer about his new role. He won’t close like he did in Kansas City, at least not regularly. But the Nationals will rely on him.

“He actually looked at me and said, ‘Wow, that’s a pretty good conversation. You’re telling me what my role is, and what I’m going to do, and how you’re going to do things.’ ” Nationals Manager Dave Martinez said. “. . . I told him, ‘Hey, we do this every day. I’ll have a conversation with you every day and let you know what’s going on.’ ”

Herrera has had plenty of difficult conversations over the last 24 hours. Around 6:30 p.m. Kansas City time Monday, Royals officials told him he had been traded. Soon after, they told him it was to the Nationals. Herrera addressed reporters later in a tearful conversation that involved many expressions of gratitude toward the Royals organization.

“The media always talked about trades and those things, but not in the middle of June,” Herrera said. “I wasn’t expecting that. I knew it was coming, but that’s why it caught me by surprise, because it was in June.”

June isn’t the time of year Nationals General Manager Mike Rizzo usually makes these kind of deals. His annual relief acquisitions have all come in July, and when he traded for Sean Doolittle and Madson in the middle of July last season, even that seemed unexpectedly early. Mid-June is not the norm, particularly as the rush on relievers had not yet begun. The Rays traded Alex Colome to the Mariners earlier this season, but several other options remained. Had Rizzo wanted to explore them, he would have waited. He did not wait, he said, because he knew what he needed.

“I think the reason you would wait out the market is to see what your needs are at the deadline. We identified our need to strengthen our bullpen early on in the season this year,” Rizzo said. “We love the back end of the bullpen but the front end of our bullpen was struggling early in the season. We thought the way we were relying on our big three or four guys, we were going to need to get some help in here.”

Rizzo said he touched base with Royals General Manager Dayton Moore about three or four weeks ago to let him know the Nationals were interested in Herrera. Talks began sporadically, then picked up in recent weeks. USA Today reported that the Angels and Dodgers were also in talks with the Royals about the reliever, whom many saw as the most enticing relief rental available.

The Nationals gave up three minor leaguers, none of whom ranked in their top 10 prospects on the mainstream lists, to get Herrera. They also paid the prorated part of his salary, around $4.4 million, which is less than they took on when they dealt for Doolittle, Madson and Kintzler last summer, but nevertheless marks a significant addition. For reference, the Nationals will pay Herrera more for four months of service than they will pay Adams for a full season.

“I think it really affects the player return, obviously,” Rizzo said. “Picking up the entire contract — the prorated portion of the contract — was important because it allows us to make the best deal we can for the long-term future of the organization.”

Picking up the money allowed the Nationals to acquire Herrera without sending any of their top prospects to Kansas City. It also leaves the Nationals in a position to continue adding to their roster, should they decide they need to do so. Rizzo was noncommittal on that point but did acknowledge that injuries have forced him to be “flexible,” though he likes the state of the roster when it’s healthy.

Herrera will make a major difference to this team, healthy or not. Martinez indicated that Herrera will close when Doolittle is overworked and will pitch key innings late when Doolittle is available for the ninth. Herrera, who has set up for such established closers as Wade Davis and Greg Holland, said he doesn’t care about when he is pitching. Everything is the same.

“I always go in the bullpen thinking how to get the batter one time each night. And that’s in whichever inning,” Herrera said. “I prepare to pitch in whichever inning with the same intensity.”

Herrera used team interpreter Octavio Martinez for his first interview as a National, which took place on the platform in the news conference room. He conducted his final interview in Kansas City in English, perhaps a sign of the comfort level he felt there. The Royals signed Herrera as a teenager out of the Dominican Republic, then converted him from starter to reliever, watching him grow into a two-time all-star in the years since he debuted in 2011. He won a World Series in Kansas City. He accumulated a 2.75 ERA and 8.9 strikeouts per nine innings during his time there. Herrera wore No. 40 in Kansas City, and he did the same with the Nationals when he jogged in from the bullpen a few hours later. Herrera threw a 1-2-3 eighth inning and touched 98.

WASHINGTON NATIONALS (38-32)

Adam Eaton RF

Juan Soto LF

Anthony Rendon 3B

Bryce Harper CF

Daniel Murphy 1B

Trea Turner SS

Wilmer Difo 2B

Spencer Kieboom C

Jefry Rodriguez P

BALTIMORE ORIOLES (20-50)

Jace Peterson RF

Adam Jones CF

Manny Machado SS

Mark Trumbo 1B

Jonathan Schoop 2B

Danny Valencia 3B

Trey Mancini LF

Caleb Joseph C

David Hess P