Zack Britton and his brother Buck have spent their entire careers in professional baseball, but they only faced each other once.

“Zack was still starting and he pitched a minor league intrasquad game,’’ said Buck Britton, who was then a minor league utility player in Baltimore’s system, while Zack was a top prospect in the organization. “My first at-bat ended in what he’d call a fly out, but I call it a lineout out to center. We never actually finished the second at-bat. I fouled off a bunch of 0-2 pitches then he threw one up and in, and then coaches ended the at-bat. They thought we were getting too competitive.’’

Though Buck, now 33, had hopes he would join his brother playing in the majors, his playing career ended when he was released by the Twins after topping out at Triple-A following the 2016 season.

Now, the brothers are eyeing another possibility, with Buck the manager at Double-A Bowie, still in the Baltimore system.

“It would be cool to see him in the majors,’’ said Zack, 31, who is in his first full season with the Yankees after arriving in a trade from the Orioles a year ago. “I definitely think he’s heading in the right direction.’’

It’s a path that started after nearly a decade playing in the minors — almost all of them with Baltimore — and he had a talk with Buck Showalter, then the Orioles’ manager.

Showalter told Zack to bring his brother to Tropicana Field when the Orioles played at Tampa Bay, since Buck Britton lived in the area.

“We talked for two hours in his office,’’ Buck Britton said. “Buck said I reminded him a little of himself.’’

When Buck Britton was still playing in the Orioles’ system, he’d spend time in major league camp during spring training and Showalter would approach him in the dugout during games.

“I’d be on the railing and out of the blue, he’d come up and ask what I’d do in that situation,’’ Buck Britton said. “He’d catch you off guard. Maybe it was to make sure you were paying attention. But he might have been trying to feel me out.’’

“He loved watching the game and he could talk about it and learn it,’’ Showalter said. “I would go up to him and ask him stuff and he would know what was going on all over the field, not just following the ball. That’s one of the things I liked about him.’’

During the conversation at Tropicana Field, Buck Britton said Showalter “told me to think about coaching.’’

“My body was breaking down,’’ Buck Britton said.

Buck Britton gave playing one more brief shot in the Dominican winter league, but soon realized it was over.

“When I got there, I knew I was done,’’ Britton said.

He started the next season as the hitting coach with Low-A Delmarva and became the manager of the South Atlantic League team last year, before a new regime got to the Orioles last offseason.

Britton was quickly bumped up to Double-A Bowie, two stops away from the majors.

He used some of his earliest work on Zack.

“I always knew he could relate to people really well,’’ Zack said. “He could coach people up. When I had some trouble in the big leagues and got sent to Triple-A, he coached me up and he was still playing there.”

Buck Britton, drafted in the 35th round out of Lubbock Christian University in 2008, remembers it a bit differently.

“I gave him a brotherly pep talk,’’ Buck said. “Actually, it was a little more stern than that. I wanted him to appreciate the opportunity he had. He saw the battle I had to try to make it as a non-prospect. I saw guys feeling sorry for themselves and I wasn’t gonna let him do that.’’

Whatever the tone, the chat worked, as Zack soon became an All-Star closer with the Orioles before landing in The Bronx last year.

Where Buck’s path leads remains to be determined.

“Wherever he’s gone, winning follows him around,’’ Showalter said of Buck Britton, whose Bowie team was 46-42 in the Eastern League heading into the weekend in a system lacking talent. “He’s got what it takes to be in the majors. We’ll see if he gets a chance there.’’

“We played together at Double-A and Triple-A and the ultimate dream was to play in the majors together,’’ Buck Britton said. “It was a good experience, but we had different careers: I was a senior sign [out of college] and he was a big prospect [drafted in the third round out of high school in 2006]. It would be great if I could get there at some point and he’s still there.’’