For two months, Mike Sullivan lived in a bubble, with a lone target in his crosshairs.

On Wednesday, with his trophy bagged, polished, and on display at Boston College High School for family, friends, and hockey fans to enjoy, Sullivan reflected on how claiming the Stanley Cup was not a solo achievement.

“What dawned on me was how many people have an influence on helping someone like myself get to the point where we were at, competing for the Stanley Cup Final,’’ said the Pittsburgh Penguins coach, who is also BC High Class of 1986.

“Also, I think they all take some small pride in the successes our team was able to enjoy. It’s amazing how many different people have an influence and impact on you. I never realized that until this year when we actually went to the Stanley Cup Final, people started to reach out. And how many people that were part of my life, from the time I was a young kid to my adult life, and how much they paid attention.’’

Sullivan, who helped initiate the Penguins’ Cup run after replacing Mike Johnston on Dec. 12, 2015, is a serious man on the bench.

The Marshfield native, now a Duxbury resident, does not hesitate to issue stern corrections to his charges.

But a tanned Sullivan could not help but smile Wednesday as he greeted family, friends, and former teammates who gathered at his old high school to pose with the Cup and shake hands with the man responsible for its arrival.

Like most who revisit old haunts with years and miles to serve as perspective, Sullivan returned to some things he did not recognize — certainly not as a student, and not even as a father to son Matt, a BC High grad now entering his senior year at Bowdoin.

“Even in the five years since he’s been gone, this place continues to evolve and change,’’ Sullivan said. “But it certainly brings me back to see some of my former teammates I played in high school with that came here today to see the Cup. To have an opportunity to share it with them is a huge thrill.’’

Sullivan was a star at BC High. As a senior, he scored 26 goals and added 33 assists in 22 games.

His high school experience allowed him to transition into a solid freshman year at Boston University, where he had 13 goals and 18 assists in 37 games. The following June, the Rangers drafted Sullivan in the fourth round.

Sullivan stayed all four years at BU. He learned to become a dependable two-way center on Commonwealth Avenue, which helped him log 709 career NHL games (77 with the Bruins during his one season here in 1997-98). Sullivan also picked up coaching tricks from Jack Parker that he would employ upon the conclusion of his playing days.

Sullivan’s coaching career included two years at the helm of the Bruins (2003-04 and 2005-06). After they chose not to retain him, he had to wait 10 years before assuming command of an NHL bench again.

“Next to my dad, Coach Parker might have the most influence on shaping my beliefs and my convictions on my philosophies of the game,’’ Sullivan said. “He was a great motivator. He was a great teacher.

“Most importantly, he really cared about his players. As hard as he was on us — he was never warm and fuzzy, I’ll tell you that — because he demanded a certain standard from all of us that played for him, we all knew it was for the right reasons.’’

The Cup spent Wednesday in Boston. There was plenty of black and gold, including the crest on Sullivan’s polo shirt. But he was wearing Penguins apparel. So were many of his visitors. Sullivan’s former employer is still waiting for its turn to host the Cup again.