On May 25, 1965, 18-year-old rookie catcher Jerry Moses became the youngest Red Sox player to hit a home run — a record that still stands — when he connected off Minnesota Twins pitcher Mudcat Grant at Fenway Park.

A star quarterback and catcher from Yazoo City High School in Mississippi, Mr. Moses had turned down a football scholarship offer from Paul “Bear’’ Bryant of the University of Alabama, choosing instead to sign with the Red Sox for a $50,000 bonus.

He played for seven Major League teams between 1965 and 1975, including his first four with the Red Sox, and while with Boston he was an American League All-Star in 1970.

“There are no better fans than the Boston fans: loyal, they know the game, if you hustle they will stand by you,’’ Mr. Moses told the Society for American Baseball Research. “They know each player and have their favorites. I have been out of baseball 36 years and still get two to three letters a week for autographs on baseball cards.’’

Mr. Moses, who previously had lived in Ipswich for many years and was passionately involved with charities including the Jimmy Fund and Genesis Fund, died Monday in High Pointe House in Haverhill from complications of aphasia and dementia.

He was 71 and resided in Rowley.

Honored in 1970 as the BoSox Club’s Man of the Year, he played in 386 Major League games, hitting .251 with 48 doubles, eight triples, 25 homers, and 109 runs batted in.

Mr. Moses hit .304 in 53 games in 1969 and was having another promising season in 1970, when he had a career-best six homers and 35 RBIs in 92 games.

But he injured his hand and was out of the Red Sox lineup the final six weeks of the season.

In early October 1970, he told the Globe that “around the clubhouse, one of the big games was making trades. We’d sit around trying to figure out who was going for who.’’

Speculation soon became reality as the Red Sox traded Mr. Moses, Tony Conigliaro, and Ray Jarvis to the California Angels in a six-player deal.

In 1987, Mr. Moses told the Globe that “you can tell I was a catcher from looking at my hands. I’ve got calcium buildup in a few fingers and I broke one of my middle fingers four times. You know, it’s a catcher’s hand.’’

Mr. Moses was a popular instructor at the summer camp he ran with Red Sox teammate and second baseman Mike Andrews, a former Jimmy Fund chairman.

“Jerry was my best friend and our families were very close,’’ Andrews said. “He was always there for the Jimmy Fund, especially through his golf tournaments. He also chaired a huge event to honor Ted Williams that took up many hours of his time and we honored him for his efforts.’’

Mr. Moses, the late Red Sox relief ace Dick Radatz, and starting pitcher Gary Bell were pranksters in the clubhouse and at Red Sox fantasy camps, where they were known as “the three amigos.’’

For Radatz’s 50th birthday, Mr. Moses hosted a gala party at the Bayside Expo.

“I only caught Dick in the bullpen,’’ Mr. Moses recalled years later, in 2005. “I spent most of my life in the bullpen — I have a PhD in bullpen.’’

His roommates in Wellsville, N.Y., during his first minor league season included future Red Sox pitcher Billy Rohr.

Rohr recalled that his best friend in Wellsville was another catcher, “and when we heard that this hotshot catcher from Mississippi was coming I made up my mind I wasn’t going to like him. Well, he wound up being best man at my wedding and I was in his wedding party. There was no pretense with Jerry. He was genuine and he didn’t have to be anyone other than himself.’’

As a Red Sox rookie, Mr. Moses, who was 6-foot-3 and weighed 205 pounds during his playing days, shared an apartment in Brookline with another rookie, pitcher Jim Lonborg.

Lonborg said Mr. Moses “was kind-hearted and a joy to be around, and had a legendary sense of humor. I still remember the $1.75 breakfasts we had at this little drugstore near our apartment. He was athletic, sound defensively — especially on balls in the dirt — and had some pop in his bat.’’

Gerald Braheen Moses was a son of Samuel Moses and the former Mary Frances Greer.

In the Society for American Baseball Research interview, Mr. Moses recalled that when he was a boy, his father was his coach and he “inspired me and my brother with great talks before our games, and about life and how to do the right things.’’

In 1968, Mr. Moses marred Carolyn Altieri of Wakefield.

Throughout his career, Mr. Moses was identified by reporters and headline writers alternately as Jerry or Gerry. His wife recalled that he often signed autographs Jerry Moses.

After hitting a home run as an 18-year-old, Mr. Moses went to the minors for seasoning and proceeded to record homers for his first hits at the Single A, Double A, and Triple A levels.

Mr. Moses held numerous charity golf tournaments at Ipswich Country Club and entered the business world after retiring as a player.

He worked for Ogden Foods and then started his own concessions company, FanFare, whose clients included the former Great Woods Center for the Performing Arts in Mansfield, the World Trade Center in Boston, and Pro Player Stadium in Miami.

He stayed on as a consultant at FanFare and was a mentor to his daughter, Kristin Reynolds, and son, Stephen, both of Ipswich, while in semiretirement.

Mr. Moses helped Stephen, a former New York Mets minor league player, found Ann’s Boston Brownie in Topsfield. With Kristen, he opened Off the Vine in Rowley.

In addition to his wife, son, and daughter, Mr. Moses leaves a brother, Rollo of Memphis; two sisters, Tiffie of Brandon, Miss., and Pam Harris of Madison, Miss.; and seven grandchildren.

A funeral Mass will be said at 10 a.m. Tuesday in Our Lady of Hope Church in Ipswich.

Mr. Moses, who saved his bat from his Major League All-Star Game, was “close with God,’’ his son said. “Faith was very important to him. He taught us to be humble and caring.’’

Stephen called his father “the best mentor I could have. He was a self-made man who loved the competition and the camaraderie of baseball, and who most of all loved his family.’’

Marvin Pave can be reached at marvin.pave@rcn.com.