PORT ST. LUCIE, Fla. -- Cam Opp speaks like an American, acts like an American and would hardly be confused for anything else in the Starbucks line. And yet within the walls of his World Baseball Classic clubhouse, Opp, a Mets farmhand pitching for Great Britain in the tournament, possesses a certain something that most of his teammates do not.

“Strangely enough, I’m probably the most British of them,” Opp said, laughing.

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For about six years, Opp lived full time in England, after his father moved the family there in the mid-2000s for an accounting job. He spent those formative times in a London suburb called Walton-on-Thames -- a place where Frederick, the Prince of Wales, supposedly played in the first recorded version of a baseball game in 1749. Outside of a plaque commemorating that event, baseball does not have a significant footprint there, nor in the whole of the United Kingdom. Soccer is king. Golf is popular, too. Opp grew up playing both.

But baseball has always been his passion. For the first decade of his life, Opp lived in Denver and Chicago, playing Little League like any other kid. When his family relocated to England, Opp continued playing baseball at an American curriculum school, where he quickly realized his skill level was beyond that of his peers. He made varsity as an eighth grader and began pitching internationally for the Great Britain U23 squad when he was 15. At one point, Opp even played for a beer-league adult team.

Yearning to test himself against higher-level competition, the left-handed Opp eventually transferred to a North Carolina high school for his junior and senior seasons, returning stateside alone while his family stayed back in London.

The rest of Opp’s story has been fraught with difficulty, as he lost his father during high school, was cut from his college baseball team, transferred to West Point, walked onto the team there, went undrafted his junior and senior seasons, played in independent ball, briefly abandoned baseball to fulfill his military commitment and then finally, in 2020, received a Minor League contract offer from the Mets.

“I’ve taken a lot of leaps of faith in this game,” Opp said.

Last year, Opp made it to Double-A Binghamton, performing well enough to catch the eye of Great Britain’s WBC organizers. He threw 1 2/3 scoreless innings in Great Britain’s qualifying round win over France, then watched his teammates upset the favored Spaniards to earn a spot in the main bracket. Now, Opp is back with that group again in Phoenix, where he will serve as a leverage reliever against some of the game’s brightest stars from the United States, Mexico, Canada and Colombia. Great Britain's first game comes against the U.S. on Saturday at 10 p.m. ET on FOX.

Pitching against the United States? Opp’s friends from West Point have jokingly taken to calling him “the Benedict Arnold of the baseball world.”

“But I didn’t live there for a day,” Opp said of his British experience, “and I think 9 to 16, 17 years old are some pretty formidable years of learning who you are.”

Opp’s ties to England indeed run deeper than those of most of his teammates, who are largely Bahamian and American. (Because King Charles is the head of state in the Bahamas, a former British colony, players from that country are eligible to compete for Great Britain in the WBC.) Of those with upper Minors experience, only one was born in the UK. Some players live overseas on a part-time basis, but Opp’s British ties run deeper. He is a dual citizen with an eye toward perhaps one day moving back to England.

For now, Opp intends to embrace the opportunity that his unique life experiences have given him.

“I served in the military. I was in the Army. That’s something I’m very proud of,” Opp said. “But I’m also proud of what I went through in England and all the stuff I learned there. That’s a big part of who I am, too.”