In letters and emails to friends and acquaintances, Lewis “Lew” Matlin would ritually close with the phrase, “Be of good cheer!”

For him, family, the sport of baseball and the relationships that developed around it in a career that spread across parts of six decades fueled much of his gregariousness in a life of 96 years.

The longtime professional baseball executive and father of University of Hawaii athletic director David Matlin died Thursday in Michigan, where he had lived in retirement.

Lew Matlin served as general manager of the Hawaii Islanders baseball team in the early 1960s, one of his most cherished memories in a front-office career that included 11 stops in the minor and major leagues that took him from Hawaii to Florida and across Canada.

“He was very outgoing, an extraordinary man who loved baseball and knew so much about it and had a photographic memory for it,” said Don Robbs, whose friendship with Matlin dated from 1964 when he was hired by Matlin to be the public address announcer at Honolulu Stadium.

“A lot of that love was passed on to his son David, who started his career with the Houston Astros before coming to UH,” Robbs said.

The elder Matlin formed an attachment to baseball after seeing Babe Ruth in a 1930 barnstorming tour and growing up in Los Angeles, where he attended Fremont High, a hotbed for the sport, with Bobby Doerr, who would become a Hall of Fame second baseman for the Red Sox.

Matlin humbly described his own playing career as “brief and ineffective” but found his calling as manager and business agent for an American Legion team in the area. Over the years he would kid Yogi Berra about being victorious in their meetings.

After serving in the Army in World War II, Matlin used the GI Bill to earn a degree from the University of Southern California, which he parlayed into a job as business manager and, later, general manager of the Bakersfield Indians of the Class C California League in 1948.

After stops in Colorado Springs, Colo.; Sherbrooke, Quebec; Jackson Beach, Fla.; Tacoma, Wash.; and Fresno, Calif., he came to Hawaii, where David was born.

He reached the major leagues with the Seattle Pilots before moving on to the Milwaukee Brewers and then, for the final 20 years of his career, the Detroit Tigers.

Matlin organized the visit to Jackson State Penitentiary in Michigan where Ron LeFlore was discovered, leading to a nine-year career in the majors for LeFlore and the movie “One in a Million.” Matlin had a bit part in the film as well as in the 1980 movie “Tiger Town,” in which he played a coach.

In Hawaii, Matlin and the late Honolulu Advertiser baseball writer Ferd Borsch began what has become an annual pilgrimage by dozens of fans to Oahu Cemetery on April 17 to mark the birthday of Alexander Cartwright, the “father of baseball,” at his grave site.

In 2016, when a report questioned Cartwright’s legitimacy to that title, Matlin, armed with historical data, led the charge to debunk the allegations.

Even in his missives to Cartwright’s doubters, Matlin would close with his standard, “Be of good cheer.”

Private family services are planned, but donations may be made to the Fred Hutchinson Cancer Center at fredhutch.org.