An undated photo of Eddie Grant of the New York Giants, who was killed in battle in World War I on Oct. 5, 1918. (San Francisco Giants)

“The Germans won’t be able to win a game from us,’’ he wrote to his sister Florence in 1918, according to Smithsonian magazine. “We would knock old Hindenburg out of the box in the first inning.’’

Eddie Grant, in fact, had appeared in the World Series, with the 1913 New York Giants. He was a Harvard-educated lawyer. And after his playing career ended, at age 33, he enlisted in the U.S. Army, leading to his most lasting distinction: He was shot while leading an effort to rescue surrounded units of the 77th Division in the Argonne Forest in northeastern France on Oct. 5, 1918, becoming the first major leaguer killed in action in World War I.

Maj. Charles Wittlesey, Grant’s friend who led the 77th Division known from the battle as “the Lost Battalion,” said of Grant: “When that shell burst and killed that boy, America lost one of the finest types of manhood I have ever known.’’

Grant first appeared in the majors in 1905 after graduating from Harvard, where he played baseball and basketball. He would play 990 games as an infielder through 1915, with Cleveland, Philadelphia, Cincinnati and the Giants. He wasn’t a great hitter —- his career average was .249 with just five home runs —- but he was regarded as a decent fielder at third base.

He also lived up to his nickname, “Harvard Eddie,’’ by earning a law degree from the university in 1909. And after retiring from baseball, he became a practicing lawyer. Less than two years later, the United States entered World War I and Grant enlisted. “I believe there is no greater duty than I owe for being that which I am — an American citizen,’’ he wrote to a friend.

Grant was killed 100 years ago Friday, at age 35, while leading the H Company of the 307th Infantry against German forces. He was one of eight major leaguers who were killed or died while serving for the U.S. military during World War I, and one of more than 50,000 Americans killed in combat during the war. According to various reports, he was badly weakened by bronchitis during the battle but refused to leave the front lines. When the Germans started attacking his troops, Grant shouted at his men to get down on the ground, while remaining on his feet to call for stretchers.

According to a letter sent to Grant’s father by Lt. Lloyd Nease, a copy of which was provided by Dean College history professor Rob Lawson, Grant’s fellow soldiers “came in looking down-hearted, and you could hear them speaking to one another, ‘The best man in the entire regiment is gone.’ ”

Grant is interred at the Meuse-Argonne American Cemetery in France along with more than 14,000 other American soldiers. Bay Area resident and World War I historian Mike Hanlon has led tours of the war’s battlefields as well as that cemetery, where he tells guests about Grant.

“He was such an engaging character,’’ Hanlon said in a phone interview. “He was a utility man — he wasn’t a baseball star. He just had this way about him.’’

So admirable that baseball Commissioner Kenesaw Mountain Landis wanted Grant added to the Hall of Fame for his service to the country. Though Grant was not inducted, he was honored in other ways. A highway in the Bronx is named for him, as well as a field at Dean College in Franklin, Mass., Grant’s hometown and the college he attended before Harvard. The Giants, with whom Grant played in the World Series and finished his career, placed a bronze plaque in his honor on the center field fence of the Polo Grounds on Memorial Day 1921. The plaque identified Grant as “Soldier — Scholar — Athlete.’’

The Giants won the World Series that year, as well as in 1922, 1933 and 1954 (the Grant plaque can be seen in some photos of Willie Mays’s famed over-the-head catch during that series). When the Giants moved to San Francisco in 1958, the Grant plaque disappeared and the team did not win a World Series for the next 52 years.

After the Giants opened AT&T Park in 2001, Hanlon wrote a letter to the team’s managing partner Peter Magowan suggesting they re-create a plaque for Grant there. Hanlon said Magowan turned it down because the club wanted to focus on its San Francisco history. But Hanlon wasn’t done. After the Giants lost the 2002 World Series in seven games, Hanlon again wrote about Grant, suggesting in an online newsletter that perhaps the relocated Giants were suffering from the “Curse of Captain Eddie.”

After installing a replica plaque in 2006, the Giants would win three World Series over the next decade.

“It’s just a story that won’t go way,’’ Hanlon said. “It’s a tragic story. Eddie is an American hero. He died in service to his country and he was doing his duty when he did it.’’

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