SOUTH PORTLAND — Becoming the next manager of the Portland Sea Dogs, or being put in charge of any professional baseball team for that matter, was never part of Billy McMillon’s ambitious five-year plan or grandiose childhood dream.

McMillon, 42, has long been content to let his talent and work ethic speak for themselves and chart that course on their own.

“Most of the things I’ve done in my life, I’ve kind of stumbled upon,” McMillon said. “I knew I wanted to stay in baseball in some capacity. (Boston Red Sox general manager) Ben Cherington gave me the opportunity. I didn’t know if I was going to be a scout, a hitting coach, but I wanted to stay into it.”

Formally introduced to the media in conjunction with the Sea Dogs’ annual Hot Stove Dinner at Sable Oaks Marriott, McMillon, hired in December, has reached the third rung of Boston’s minor-league managerial ladder in only his fifth season.

He succeeds Kevin Boles, who advanced to Triple-A Pawtucket after PawSox manager Gary DiSarcina ascended to the role of third base coach with the Los Angeles Angels.

McMillon’s experience includes two-year tenures with the Greenville Drive and Salem Red Sox. Salem won the 2013 Carolina League championship, finishing the season with an 11-game winning streak, including playoffs.

“Things like that have happened in my career. I kind of thought I was going to be a hitting coach, and I got asked to be a manager,” said McMillon, who spent two years as Greenville’s hitting instructor before his managerial breakthrough. “Then I got asked to come to Double-A. I don’t think my goal the past couple years was to get to Double-A as a manager. I think it just happened. I let somebody else reward me.”

Part of that reward is returning to one of his early professional baseball haunts. McMillon, the 11th manager in the Sea Dogs’ 21-year history, is the first to have previously played for the team.

He was the centerpiece of a 1995 club — then affiliated with the Florida (Miami) Marlins — that included Charles Johnson, Mike Redmond, Edgar Renteria, Matt Mantei and Antonio Alfonseca. McMillon batted .313 with 14 home runs and 93 RBIs, leading the Eastern League with 162 hits. He was selected to the all-star team and was named the Marlins’ minor league player of the year.

Managed by Carlos Tosca, that team and its 86-56 record still stand as the best in Sea Dogs history. But the season also produced one of McMillon’s greatest pro disappointments, a best-of-five loss to New Haven in a semifinal series.

“If memory serves we were in first place from day one the whole year, and we just kind of ran out of gas at the end,” McMillon said. “I think maybe guys were looking toward the offseason and assuming we were going to win. That was probably one of the best teams I’ve played on. A lot of guys got to the major leagues off that team.”

McMillon made his major league debut on July 26, 1996 and spent portions of seven seasons with four teams — the Marlins, Philadelphia Phillies, Oakland A’s and Detroit Tigers.

Born in New Mexico, McMillon, who played his high school and college ball (Clemson) in South Carolina, hit 16 home runs in 269 MLB games.

Again, it was the realization of a dream that developed gradually.

“When I was in high school, I was playing in a tournament and did really well, but I was thinking about playing high school baseball,” McMillon said. “As I’m walking to our bus, a college coach comes up to me and I said, ‘Whoa, I could play college baseball.’ I didn’t even think about professional baseball. It seemed like it was so, so far away. Fast forward, I go to college and I see these professional baseball players coming back to work out with us. I thought my skills matched up pretty well with those guys.”

McMillon said he believes the Red Sox projected him as a manager because of his even temperament and his ability to get along with all personality types.

He characterizes himself as a “player’s coach” and is quick to recognize former Red Sox manager Terry Francona as one of his strongest influences. Francona managed McMillon with the Phillies in 1997.

“I remember him being kind of laid-back, developing relationships with the players. Even me, not being a Phillies draft guy but somebody they acquired, he kind of embraced me and took me under. I really appreciated that,” McMillon said.

McMillon said he is more uneasy about returning to the cold, early-season weather and endless bus rides of the Eastern League than any adjustments he may have to make as a Double-A manager.

The memories of his one season at Hadlock Field are admittedly foggy after two decades, but McMillon recalls a warmth from the bleachers that balanced out those cold winds blowing in from the Gulf of Maine.

“I remember that there were always a lot of people and that they were all into the game,” he said. “I drove around Portland today and nothing seemed familiar. But I suspect that once I get up here and into it, things will start coming back to me.”