He is the second of only two Major League Baseball players to have died as a result of an injury received in a game (the first was Mike "Doc" Powers in 1909); Chapman was hit in the head by a pitch thrown by Yankees pitcher Carl Mays. His death led Major League Baseball to establish a rule requiring umpires to replace the ball whenever it became dirty. His death was also one of the examples used to emphasize the need for wearing batting helmets (although the rule was not adopted until over thirty years later). His death was partially the reason MLB banned the spitball after the season.
Chapman led the American League in runs scored and walks in 1918. A top-notch bunter, Chapman is 6th on the all-time list for sacrifice hits. Only Stuffy McInnis has more sacrifices for right-handed batters. Chapman was also an excellent shortstop who led the league in putouts three times and assists once. He batted .300 three times, and led the Indians in stolen bases four times. In 1917, he set a team record of 52 stolen bases, which stood until 1980. He was hitting .303 with 97 runs scored when he died.
At the time of Chapman's death, "part of every pitcher's job was to dirty up a new ball the moment it was thrown onto the field. By turns, they smeared it with dirt, licorice, tobacco juice; it was deliberately scuffed, sandpapered, scarred, cut, even spiked. The result was a misshapen, earth-colored ball that traveled through the air erratically, tended to soften in the later innings, and as it came over the plate, was very hard to see.
This practice is believed to have contributed to Chapman's death. He was struck by a pitch by Carl Mays on August 16, 1920 in a game against the New York Yankees at the Polo Grounds. Mays threw with a submarine delivery, and it was the top of the fifth inning, in the late afternoon. Eyewitnesses recounted that Chapman never moved out of the way of the pitch, presumably unable to see the ball. "Chapman didn't react at all," said Rod Nelson of the Society of American Baseball Research. "It was at twilight and it froze him." The sound of the ball smashing into Chapman's skull was so loud that Mays thought it had hit the end of Chapman's bat, so he fielded the ball and threw to first base. Chapman died twelve hours later in a New York City hospital, at about 4:30 a.m. He was replaced by Harry Lunte for the rest of the game.
In tribute to Chapman's memory, Cleveland players wore black arm bands, with manager Tris Speaker leading the team to win both the pennant and the first World Championship in the history of the club. Rookie Joe Sewell took Chapman's place at shortstop, and went on to have a Hall of Fame career (which he, ironically, concluded with the Yankees).
Not long after Chapman died, a bronze plaque was designed in his honor. The plaque features Chapman's bust framed by a baseball diamond and flanked by two bats, one of them cradling a fielder's mitt. At the bottom of the tablet is the inscription, "He Lives In The Hearts Of All Who Knew Him." The plaque was dedicated and hung at League Park and later at Cleveland Municipal Stadium before being taken down for unknown reasons.
Jim Folk, a former vice president of Indians operations, said, "It was in a store room under an escalator in a little nook and cranny. We didn't know what we were going to do with it, but there was no way it was just going to stay there when we moved to Jacobs Field. We had it crated up and put on a moving truck and it came over along with our file cabinets and all the other stuff that came out of the stadium."
In February 2007, the neglected plaque was re-discovered by workers cleaning out a storage room at Jacobs Field. Covered by years of dust and dirt, the bronze surface had oxidized a dark brown; the text was illegible. The plaque was refurbished and hung in Heritage Park, an exhibit of Indians history at Progressive Field.
The historical novel, The Curse of Carl Mays, by Howard Camerik, also recounts the Chapman-Mays incident.
The Dan Gutman novel Ray & Me, tells the story of the Chapman incident with a fictional touch as the main character Joe Stoshack travels back in time to try to prevent his death.