Brandon Kintzler is a Cub. (Scott Taetsch/Getty Images)

Brandon Kintzler did not report to Nationals Park on Tuesday afternoon thinking he had played his final game for the Washington Nationals. The trade deadline was approaching, but he thought he was safe. The reliever prepared for the club’s game against the New York Mets as usual. Then, about an hour before the 4 p.m. nonwaiver trade deadline, he was summoned to Manager Dave Martinez’s office.

“Am I getting traded?” Kintzler asked.

He was, he was told. Kintzler thought it was a joke.

“Pretty shocked,” he said.

After all the speculation swirling around the organization over the previous 24 hours, the only trade the Nationals completed before Tuesday’s deadline was shipping Kintzler to the Chicago Cubs, a National League playoff contender, for Jhon Romero, a minor league right-hander who hasn’t pitched above Class A. He owns a 3.27 ERA in 32 relief appearances for the Cubs’ high-A affiliate. He isn’t helping the big league club anytime soon.

On the surface, trading Kintzler for a low-level prospect while keeping the rest of the team intact to make a run for a postseason berth is not sensible. The Nationals acquired Kintzler at the deadline exactly a year earlier as part of their midseason bullpen overhaul. He teamed up with Sean Doolittle and Ryan Madson to solidify Washington’s relief corps last year. He was a valuable piece last season and has been this season. He has a 1.88 ERA in 14 1/3 innings since June 28. That was good enough for the Cubs, the National League Central’s first-place club, to add him.

“I felt like I was throwing the ball well,” Kintzler said. “I can go help a contender, another contender, right now. I don’t know. Just shellshocked right now. At a loss for words.”

The Nationals gave their reasons for trading Kintzler publicly, but a significant reason went unspoken. Club officials believed Kintzler was an anonymous source for reports that cited clubhouse strife, according to people with knowledge of the situation. In a radio interview on 106.7 The Fan on Wednesday, Kintzler denied he was a source for Yahoo’s recent story, which called the Nationals’ clubhouse “a mess.”

“I’ve never talked to that [author] Jeff Passan guy in my life, so that’s an interesting accusation,” Kintzler said on “Grant & Danny.” “I know for a fact that someone got him to admit his source was not a player, so it wasn’t me. I’ve never talked to that guy in my life.”

Martinez said the reason Washington traded Kintzler was to give the spot to Wander Suero, who can pitch multiple innings and provide length. Suero was called up from Class AAA Syracuse about an hour before Tuesday’s game against the Mets. Martinez said the club figured Madson, recently acquired Kelvin Herrera and Sean Doolittle, whenever he comes off the disabled list, composed a strong enough back end. Dealing from that surplus allowed the team to address another need, Martinez explained.

“I think that’s missing in the bullpen,” Martinez said. “Look, Brandon was awesome. He got some big outs for us, he really did. Of course, he’s going to be missed in the bullpen, but I think moving forward having some length to go with [Matt Grace] is important. It really is.”

Nationals General Manager Mike Rizzo said he believed Suero deserved a spot in the majors and will be a vital piece in the future. The 26-year-old Suero has pitched to a 3.15 ERA in 16 games in a couple stints for the Nationals this season. He lasted appeared in a game for Washington on July 14, when he tossed 2 2/3 scoreless innings.

Rizzo hinted that Koda Glover, who has made eight minor league appearances after missing the season’s first four months with a shoulder injury, could join the team soon to bolster the bullpen. He also suggested moving Kintzler was, to some extent, financially motivated. Kintzler has a mutual option for next season; if the team doesn’t pick up a $10 million team option, he can pick up a $5 million player option.

“It gives us financial flexibility, this year and next year going forward,” Rizzo said. “And we felt it was the prudent move, like all the moves we make, with 2018 and beyond in mind.”

That mutual option is part of the contract Kintzler signed with the Nationals in December. He received offers on the table from other teams for more money and a more prominent role, but chose the Nationals because he liked the clubhouse and the organization. He felt at home. Teammates got along with him. He was close with Doolittle and Max Scherzer, often bouncing ideas off them.  He played the role of pitching coach, helping Tanner Roark and Gio Gonzalez with their mechanics during their struggles this season. His presence was felt.

“He helped me a lot in my career just in the years that we spent together so I’m going to miss him,” Doolittle said. “We’re going to miss his ability on the field. I think we’re going to miss him in the clubhouse as well.”

But he also rubbed some people the wrong way because he was willing to speak his mind more than others. Perhaps that was the lone  factor in the Nationals’ decision. Regardless, Kintzler is a Cub now, and he didn’t see it coming.

“In the beginning, you care because it’s your character,” Kintzler said. “I work really hard, I feel like, to be a good teammate. I always thought I was a good teammate and everyone in that clubhouse thought I was a good teammate. When someone tries to say something about your character as far as how you are in the clubhouse, that hurts a little bit, but it’s just an opinion of one person and they can think what they want. I thought I did a good job there. New beginnings today and it is what it is. Put it behind me and I can’t wait to face them next week.”

Scott Allen contributed to this report.

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