WASHINGTON -- Best friends and former teammates Hunter Harvey and Ryan Mountcastle met for dinner on Monday night, before the Beltways Series kicked off its second leg on Tuesday night at Nationals Park. There, Harvey was “just talking smack,” jokingly promising that should an at-bat between them arise, he’d plunk Mountcastle in the back. Call it payback for years of roommate antics in the Minor Leagues.

“The dude was in my wedding,” Harvey said following the Nats’ 4-3 loss to the Orioles. “I talk to him about every night. So when he got in the box, I was like, ‘Oh, here we go.’ I just couldn’t calm down.”

Harvey had not allowed a home run all season as a standout reliever for the Nationals, nine years after being drafted in the first round by the Orioles. That streak came to an end when he allowed his first dinger in 30 innings to, of all people, Mountcastle.

“I got him, man,” Mountcastle smiled, “and it's probably one of my favorite home runs I've ever hit.”

As Mountcastle crossed first base, having turned a 99.2 mph pitch from Harvey 395 feet to right-center, he took a look at the mound in the corner of his eye. He was looking for eye contact. Harvey could only break out in laughter -- something he wouldn’t fathom doing if anyone else was responsible for the homer.

“That’s the first time I ever laughed giving up a home run,” Harvey said. “I just couldn’t -- it was hard to kind of hide that emotion, just because we’re so close and we talk so much trash. When that happened, he looked at me and he was laughing. … I was like, ‘This is the worst-case scenario.’”

For Mountcastle, the home run was essential for far more than bragging rights. It was another sign of the turnaround he hopes to be showcasing in September -- he now has four homers in the month after compiling just five during July and August, and he added a single and two walks on Tuesday. It was also a game-tying swing, setting up Austin Hays’ go-ahead double later in the inning to propel the Orioles to victory. Most important: the victory brought them to five games back of the third and final AL Wild Card spot.

“Those were the best at-bats he's taken in months,” said Orioles manager Brandon Hyde. “The walks, the ability to lay off some breaking balls down, tough pitches, go deep in the count and turn around 100 into right-center … he showed you tonight what he's capable of.”

The home run to Mountcastle was a rare blemish on Harvey’s bounceback season. He entered the Beltway Series with a 2.79 ERA, a 1.10 WHIP and a 1.71 FIP in 29 appearances this season. His ERA had dipped to 1.88 in his past 13 games, which included a win and a pair of holds.

The 27-year-old has attributed his performance to health. His tenure with the Orioles, in contrast, was hampered by injuries. The 22nd overall pick in the 2013 Draft, Harvey pitched just 23 2/3 frames for the O's across three seasons. He was claimed off waivers by the Giants on Nov. 5, 2021, released on March 14 of this year and was claimed off waivers by the Nats a week later. After missing 73 of Washington’s games with a right pronator strain, Harvey has been full-go for the second half of the season.

So after all that, facing his former team for the first time came with a rush of emotions.

“I mean, that was like debut adrenaline,” said Harvey. “It don’t come around very often. It’s hard to say, ‘This is how you handle that.’ I tried to get out of the middle as much as I could, but of course the one guy I couldn’t is the worst guy possible.”

That person also turns out to be one of Harvey’s biggest supporters.

“I'm so happy for him, man,” Mountcastle said. “He's pitched great all year for them. I hope he keeps doing well, and [I] wish him nothing but the best.”

The Orioles, fond friends of both players in the at-bat, took front seat in the clash of titans.

“That was a battle we were all on the top step, looking forward to seeing just power against power,” said Hays, another former teammate of Harvey’s, “and Mounty came out on top in that one.”

Harvey only had a few seconds after returning to the clubhouse to scroll through his phone. He estimated that he had about 100 messages waiting for him, including a few from Mountcastle. As he concluded his media session with reporters at his locker, his phone started going off again.

“Incoming call: Ryan Mountcastle.”