He played for the Cleveland Indians, Minnesota Twins, Los Angeles Dodgers, Montreal Expos, St. Louis Cardinals, Oakland Athletics, and Pittsburgh Pirates from 1958 to 1971.

He pitched two complete-game World Series victories in 1965, hit a three-run home run in game 6, and was named The Sporting News American League Pitcher of the Year.

He attended Moore Academy in nearby Dade City, where he played football, basketball, and baseball.

[6] He made his MLB debut on April 17, 1958, at the age of 22,[4] winning a complete game against the Kansas City Athletics.

He and Zoilo Versalles were traded by the Twins to the Dodgers for John Roseboro, Ron Perranoski, and Bob Miller on November 28, 1967.

On his official website, Grant paid tribute to the black major-league pitchers (including himself) who won 20 or more games in a season.

[15] In 2007, Grant released The Black Aces, Baseball's Only African-American Twenty-Game Winners,[16] featuring chapters on each of the then-13 black pitchers to have at least one twenty-win season, and also featuring Negro league players that Grant felt would have been twenty-game winners if they had not been excluded by the baseball color line.

In February 2007, during an event to honor Black History Month, President George W. Bush honored Grant and fellow Aces Ferguson Jenkins, Dontrelle Willis, and Mike Norris, and the publication of the book, at the White House.

[17] Grant threw out the ceremonial first pitch on Opening Day at Progressive Field in Cleveland on April 14, 2008, to commemorate the 50th anniversary of his major-league debut; he was also awarded the key to the city to honor the occasion.