PHILADELPHIA -- The visiting bullpen in Citizens Bank Park is elevated, exposed and a glaring target.

Relief pitchers can sit on a bench under cover, but that doesn’t protect them from every angle. Hecklers retain a view from either short side of the rectangular configuration. In short, nowhere, and no one, is safe out there.

Merge the bullpen’s open position with some of the sport’s surliest fans and an idea emerges: this could be the most volatile bullpen spot in baseball. Add Bryce Harper leaving Washington for Philadelphia, a three-game series early in the season with both teams competitive and the situation stirs further.

“There’s other bullpens where you’re really close with the fans,” Sean Doolittle told NBC Sports Washington. “I think like Seattle, you’re really close. San Diego they’re right behind you. There’s other ones. Tampa. Oakland.

“But, they call it the City of Brotherly Love for a reason.”

Fans in town have famously booed Santa Claus. Wednesday, they were busy grousing at the home team, even booing relief pitcher Juan Nicasio when he struck out. Nicasio is a career .123 hitter who strikes out half the time. Washington won, 15-1.

Chants of “Juan, you suck!” temporarily spread through the stadium Tuesday -- aimed at Juan Soto, not Nicasio. Monday was mostly spent lauding Harper’s existence.

Meanwhile, various conversations were taking place out in the bullpen. One fan attempted to mock reliever Kyle Barraclough for Harper’s arrival in Philadelphia. Barraclough never played with Harper, nor is he the team’s general manager. He was confused and amused during the series.

“There’s some aspects of the bullpen location that are prevalent in other stadiums, but you add in the fans that are out there yelling at you, what they’re saying, what they’re doing -- kind of relentless in a way,” Barraclough told NBC Sports Washington. “Which, I mean, that’s baseball. You’ll get that. It makes it a more fun environment sometimes as long as it doesn’t get too personal. If those things being said aren’t really hitting home, if they are keeping it light-hearted, ‘You suck. You’re going to give it up,’ that’s fine.”

Doolittle’s situation -- as always -- was different. He grew up a Phillies fan in nearby Tabernacle Township, New Jersey. Important childhood topics included baseball, diners and high school pride. The well-versed fans lurking around the bullpen engaged Doolittle on these subjects during the Nationals’ three days in Philadelphia.

He was told Lenape and Cherokee High Schools were both superior to where he graduated, Shawnee.

“They were very proud of their high schools and letting me know about it,” Doolittle said.

The All-Star closer attempted to sway diner opinions by stating Medport Diner in Medford, New Jersey -- a 4.0 according to Google reviews -- was the gold standard of south Jersey diners. For wings, the Pic-A-Lilli Inn is king. He shouted such thoughts at those hanging on the railing who vehemently disagreed.

He also had another question for the ticket-bearers present during this first three-game series of 2019 between the Nationals and Phillies: Where were they before?

“I said, ‘Where have you guys been? You weren’t here last year. Were you guys Nationals fans last year? What’s the deal?’” Doolittle said. “He was like, ‘We were here last year.’ I was like, ‘No, you weren’t. Since I’ve been coming here for two years, you guys weren’t here, I promise.’ He said, ‘We were here, we just sat in our seats.’ I thought it was pretty funny.”

The park’s famous “Dollar Dog night” delivered long lines in the stadium and nostalgia for Doolittle. He previously would “crush double-digit” hot dogs when coming as a fan. Tuesday, an old high school friend of his, armed with dollar dogs, shouted down to see if he wanted one Doolittle declined since it was possible he had to work later that night. His friend told him it was 6-1, there’s no way he was going in, have a dog. Doolittle recorded a five-out save in the wild extra-inning win thankful he declined.

In all, the spot invites engagement with a fan base considered rough and passionate. Barraclough said he tries to find whatever cover possible. Matt Grace tries keep a straight face and comfortable distance. Doolittle tries to disarm some fans with his geographical familiarity and willingness to talk back.

“I know what their shtick is,” Doolittle said. “Doesn’t work on me. I don’t know -- I like to have fun with them. But you do have to do a quick assessment. There are some fans that are way over board. There are some, they’re having a good time and they’re trying to give you a little bit of grief. You can have fun with those people because they’re not taking it too seriously. There are some people you’re just kind of like -- OK, I’m going to go down to the other end of the bullpen for a little while. They’ll scream themselves hoarse. Most of the time, it’s all in good fun. Even here.”

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