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By Steven Zaitz

John DeMartini, an educator in the Northport School district for more than half a century, has died at the age of 81. 

Larger than life, yet at the same time unassuming, DeMar, as he was known to everyone in his orbit, was a physical education teacher and Northport High School head baseball coach from the mid 1980s to 2018, won 350-plus games as Tiger skipper, but more importantly enriched the lives of countless students, families and fellow faculty over the course of his 57 year career.

Born in the Bronx, DeMartini moved to Westbury as a boy and attended W.T Clarke High School and then Adelphi University, where he was pitcher and an outfielder on the Panthers baseball team. In 1966, he became a teacher and basketball coach in the Northport-East Northport School District, taking over as Tiger head baseball coach in 1985; a position he held for 33 years until an issue with his heart required him to take an extended leave of absence.

Sean Lynch, an assistant coach at that time and one DeMar’s best friends, took over the team in 2019 as DeMartini recovered from his illness. The two men shared an office for 25 years.

“The most important thing that John took pride in, is the many great relationships that he built over the years and the impact that he had on so many lives,” Lynch said. His love for the kids and the people he touched so positively were always the most important thing to John over wins and losses, and I think that’s truly what his legacy is and will always be.”

One of those kids is NHS Class of 2019 Trent Mayer, who has recently begun a career in education as a teacher in the Franklin Square School District. He also serves as both the Northport Junior Varsity Boys volleyball and baseball coach.

“As I begin my journey as a physical education teacher and coach, I carry with me the invaluable lessons DeMar taught me,” said Mayer. “He always emphasized the importance of being myself and connecting with students. His last words to me were ‘kids don’t care how much you know, until they know how much you care.’ This has become my guiding principle. I aim to create a supportive environment where students feel valued and inspired and DeMar’s mentorship has shaped not just my career, but my outlook on life. I am grateful for his guidance and proud to continue his legacy.”

DeMartini’s legacy is multi-generational, as current Northport Baseball Booster Club president and baseball mom Noelle Hardick, Class of 1992, can attest. Her eldest son Thomas was the Tigers’ starting second baseman in 2024 and he graduated last spring. Michael Hardick, an outfielder, will graduate in 2026 and both Hardick boys started playing in summer baseball camps led by DeMartini when they were 5 years old

“Coach DeMartini has and always will be the heart and the face of Northport baseball,” Mrs. Hardick said. “He was the coach when I was a student there and was a huge part of not only the baseball team, but the whole school and community. Everyone in the Northport community knows DeMar. That’s something really special and it’s something that you can’t fake or make up. He was the most genuine, loving, kind and selfless person.”

One of DeMartini’s longest relationships was with legendary girls basketball coach Rich Castellano, who has over 750 wins in his career, many of which were witnessed by DeMartini, who was often perched behind the visiting team’s bench to watch Castellano’s girls do their thing.

The two men met in 1976 and quickly became close friends. In recent years, they were often spotted riding around the Northport campus in golf carts, ostensibly to monitor practices and games, but more often to spread good cheer to other student-athletes or anyone lucky enough to cross the path of their cart.

“I promised him that nobody is going to take his name of that golf cart,” an emotional Castellano said. “John’s heart was always with kids and his team, and he was just a good friend that way. The kids loved him for it. He was like a kindly grandfather to these kids and had a huge following. We all saw that when we dedicated the field to him and so many kids, event ones that graduated, made it back for that ceremony to celebrate not just the field-naming, but to celebrate the man.”

On a sunny Saturday morning in September of 2021, the NHS baseball field was named in DeMartini’s honor. Tiger baseball stars past and present came to the ceremony to reminisce, embrace DeMar and shake his hand, and then see his name across the top of the scoreboard in big block letters. 

Rows and rows of folding chairs were spread across the infield for family and VIPs as hundreds of students, parents and faculty cued both the foul lines from home plate to the outfield. Northport Athletic Director Marc Dantuano spoke, as did fellow coaches Jim DeRosa, Lynch and Castellano, along with a few former Tiger players. 

DeMar, the final speaker of the morning, was moved to tears as he finished his speech. As he stepped down from the podium, he doffed his cap to the crowd of close to 1,000.

“It’s always been his field,” said Lynch. “That ceremony just made it official. It was a great day.”

Class of 2023 grad John Dwyer, who played first base and catcher for Northport and is now playing baseball at the Massachusetts Institute of Technology, was at that ceremony. When the coach returned from his heart issue in 2019, he became the Tiger pitching coach and thus, he and Dwyer, along with the pitching staff, would spend a lot of time together trying to gameplan a way to get opposing hitters out.

“Coach DeMar was such a kind and extremely dedicated man, who put a tremendous amount of time and energy into the baseball program, the school, and the community as a whole,” Dwyer said. “He really cared about each person he encountered and looked to put a smile on their face with his great sense of humor.  He impacted so many people over the years and we’re all going to miss him a lot.”

One of the last conversations Lynch had with DeMartini was a few days before he passed. DeMar had developed a succession of ailments and did not fully disclose how serious they were, as he did not want anyone to worry. 

At the time, Lynch did not realize it would be their last conversation.

“My phone created a memory that day of a photo of DeMar and me, so I texted it to him. I thought it would raise his spirits,“ Lynch recounted. “As the conversation went on, he told me that he wasn’t sure that he would be able to get back this year to help out with the baseball team. He then said ‘Just make sure nobody forgets about me.’ I thought he was speaking in the context of this season, so I assured him that nobody was going to forget about him, and I told him that he would soon be back out there on his field where he belongs. That was the last conversation we had.”

Demar may no longer set foot on his namesake field, or sit in the dugout, or make a trip to the mound to give his pitcher an encouraging pat on the behind, but his legacy and impact on the Northport community will never fade from it.

John is survived by his sister, Lynn McDonald, and her husband, Stephen McDonald, along with his nephew Justin McDonald and his family, Erica (wife), Chloe (daughter), and Harper (daughter). In lieu of flowers, if you wish, you can make a donation to the Northport High School Baseball Booster Club, 9 Tanager Lane, Northport, NY 11768 – Checks should be made out to NHS Baseball Booster Club and in the memo line please write DeMar.