Born in Lynn, Massachusetts, Agganis was both a baseball and football High School All American. He starred in both football and baseball at Boston University, at quarterback and at first base. After a sophomore season in 1949, when he set a school record by tossing fifteen touchdown passes, he entered the Marine Corps. Agganis played for the Camp Lejeune (N.C.) football and baseball teams. He received a dependency discharge from the Marines to support his mother and returned to college to play in 1951-52. Agganis became the school's first All-American in football.

Agganis set another Boston University mark by passing for 1,402 yards for the season and won the Bulger Lowe Award as New England's outstanding football player. Coach Paul Brown of the Cleveland Browns thought he could be the successor to Otto Graham and drafted the college junior in the first round of the 1952 NFL draft, offering him a bonus of $25,000. Boston Red Sox owner Tom Yawkey outdid Brown, however, and signed Agganis to play Major League Baseball for the Red Sox as a first baseman for $35,000.

Following his 1953 college graduation, he played with the Triple-A Louisville where he hit 23 home runs with 108 RBI and batted .281. He made his major league debut on April 13, 1954. Agganis had a modest rookie campaign, though he did lead AL first basemen in assists.

In 1955, Agganis was off to a good start when tragedy struck. On June 2, he was hospitalized with pneumonia after complaining of severe fever and chest pains. Though he rejoined the Red Sox ten days later, he fell ill again in Kansas City on June 27 and was flown back to Cambridge, Massachusetts, where he died of a pulmonary embolism. Harry Agganis was 25 years old. Ten thousand mourners attended his wake. He was inducted into the College Football Hall of Fame in 1974. Gaffney Street, near the former site of Braves Field in Boston, was renamed Harry Agganis Way in his honor on November 11, 1995.

Harry Agganis was named by Harry Cleverly as 1st baseman on his All-Time Baseball team.

Graduated: 1954
Inducted: 2008