Grant graduated from Harvard in 1905 and was given a tryout by Cleveland. He got three hits his first game, but was hitless the next day against Cy Young and was dropped to the minors. He reappeared with the 1907 Phillies, and took over as leadoff batter in 1908, leading the NL in at-bats in 1908 and 1909. Grant became a fine-fielding third baseman, fast on the bases and dependable in the clutch. After two-and-a-half seasons with the Giants, he retired in 1915 to practice law in New York City.
In World War I, he led a mission in the Argonne Forest offensive to rescue the “Lost Battalion” trapped behind German lines. When he met with machine gun fire, he became the only ML player killed in wartime action. A monument to his memory was placed in the Polo Grounds deep centerfield, and each Memorial Day there was a wreath-laying ceremony at his plaque.