b. December 21, 1859 · Catcher who batted .175 across three clubs, 1878 to 1886.

b. December 21, 1861 · Catcher who batted .240 across four clubs, 1883 to 1891.

b. December 21, 1882 · Baseball figure for the Boston Rustlers, 1911 to 1911.

b. December 21, 1887 · Center fielder who led the National League in home runs four times and was the first player in the league to reach 200.

b. December 21, 1897 · Led the National League with five saves in 1928 after nine years outside the majors.

b. December 21, 1900 · Pitcher for the Cleveland Indians, 1922 to 1922.

b. December 21, 1911 · Twelve home-run titles, as many as Babe Ruth, and nine in runs batted in, more than anyone else has won.

b. December 21, 1920 · Pitcher across three clubs, 1949 to 1954.

b. December 21, 1925 · Pitcher who won 127 games with a 3.65 ERA across three clubs, 1948 to 1960.

b. December 21, 1930 · Catcher who batted .236 across two clubs, 1956 to 1960.

b. December 21, 1948 · Hit 442 home runs and batted .236, and hit 35 in his final season without being offered another contract.

b. December 21, 1960 · Center fielder who batted .274 across four clubs, 1983 to 1995.

b. December 21, 1972 · Pitched twenty-one seasons for eleven clubs after failing for six years as a starter.

b. December 21, 1972 · Pitcher across six clubs, 1995 to 2006.

b. December 21, 1977 · Pitched in 150 games across nine seasons spread from 1999 through 2015.

b. December 21, 1977 · Second baseman who batted .263 across seven clubs, 1999 to 2007.

b. December 21, 1978 · Pitcher across two clubs, 2001 to 2004.

b. December 21, 1985 · Pitcher across two clubs, 2010 to 2019.

b. December 21, 1988 · Pitcher across four clubs, 2015 to 2021.

b. December 21, 1988 · Catcher for the St. Louis Cardinals, 2015 to 2015.

b. December 21, 1988 · Pitcher for the Kansas City Royals, 2011 to 2021.

b. December 21, 1989 · Pitcher for the Seattle Mariners, 2015 to 2016.

b. December 21, 1996 · Pitcher for the Miami Marlins, 2022 to 2022.

b. December 21, 2002 · Pitcher for the Arizona Diamondbacks, 2024 to 2025.

d. December 21, 1909 · Pitcher for the Cincinnati Kelly's Killers, 1891 to 1891.

d. December 21, 1912 · Pitcher across three clubs, 1884 to 1889.

d. December 21, 1912 · Third baseman for the Cleveland Spiders, 1893 to 1893.

d. December 21, 1936 · Catcher for the Cleveland Blues, 1879 to 1879.

d. December 21, 1942 · Shortstop for the New York Giants, 1899 to 1899.

d. December 21, 1943 · Catcher who batted .249 across seven clubs, 1895 to 1908.

d. December 21, 1943 · First baseman for the Kansas City Cowboys, 1884 to 1884.

d. December 21, 1946 · Pitcher for the Pittsburgh Pirates, 1916 to 1919.

d. December 21, 1950 · Right fielder across two clubs, 1890 to 1890.

d. December 21, 1957 · Shortstop who batted .233 across three clubs, 1911 to 1915.

d. December 21, 1963 · Pitcher across three clubs, 1901 to 1906.

d. December 21, 1963 · First baseman for the New York Yankees, 1913 to 1914.

d. December 21, 1964 · Baseball figure for the Chicago White Sox, 1914 to 1914.

d. December 21, 1970 · First baseman who batted .274 across two clubs, 1936 to 1943.

d. December 21, 1978 · Third baseman across three clubs, 1912 to 1916.

d. December 21, 1985 · Pitcher across two clubs, 1922 to 1930.

d. December 21, 1987 · Pitcher for the Philadelphia Athletics, 1915 to 1915.

d. December 21, 1993 · Left fielder for the Philadelphia Athletics, 1945 to 1945.

d. December 21, 1993 · Second baseman for the Philadelphia Phillies, 1940 to 1940.

d. December 21, 2005 · Catcher who batted .220 across three clubs, 1968 to 1979.

d. December 21, 2007 · Pitcher across seven clubs, 1962 to 1968.

d. December 21, 2011 · Third baseman across two clubs, 1963 to 1964.

d. December 21, 2012 · Shortstop for the Brooklyn Dodgers, 1943 to 1943.

d. December 21, 2023 · Pitcher for the Philadelphia Phillies, 1967 to 1967.