Born in San Francisco, CA, James Edward Gentile was signed by the Brooklyn Dodgers as a high school pitcher in 1952. He played his first minor league season as a pitcher, earning a 2-6 win-lost record. The next year he was converted into a first baseman. He languished for eight years in the minors for a Dodgers team that already had All-Star Gil Hodges at first base and Norm Larker. He dominated the minors, leading two separate leagues in home runs.

Gentile was traded to Baltimore in 1960, where he was named to the 1960 All-Star Game his first full season. He enjoyed his best season in 1961, hitting career-highs with a .302 batting average, 46 home runs, 141 runs batted in (see below), 96 runs, 147 hits, 25 doubles, 96 walks, .423 on-base percentage, .646 slugging average, 183 OPS+ and 1.069 OPS. His amazing season was largely overshadowed by the Yankees' Mantle and Maris pursuit of the All-time HR record. Jim finished third in MVP balloting (behind Mickey Mantle and Roger Maris). In addition, He hit five grand slams — including two straight in one game — setting an American League record that stood until Don Mattingly belted six in 1987.

Gentile's 141 RBIs in 1961 was second only to Roger Maris' 142 RBIs, however, analysis by the Society for American Baseball Research determined Maris was incorrectly credited with an RBI in a game on July 5, 1961. Maris reached base on an error by numerous accounts. Therefore, Gentile and Maris both had 141 RBIs in 1961. Gentile's contract with the Orioles in 1961 called for a $5,000 bonus if he led the league in RBIs. The Orioles made good on that deal 50 years later and presented Gentile with a check for $5,000 at a game in 2010. Though he spent just four seasons in Baltimore, the Orioles inducted Gentile into their Hall of Fame in 1989.

Jim was named to 6 All-Star teams in 3 years, and finished second in Rookie of the year voting in 1960.

Following his major league career, he played one season in Japan for the Kintetsu Buffaloes in 1969. Gentile managed minor league teams the Fort Worth Cats and the 2005 Mid-Missouri Mavericks.

What if Diamond Jim had not wasted 8 years tearing up the minor leagues? Hall of Fame?

(excerpted from SABR, BR Bullpen and Wikipedia)