Mordecai Peter Centennial Brown (October 19, 1876 – February 14, 1948), nicknamed Three Finger or Miner, was an American Major League Baseball pitcher and manager during the first two decades of the 20th century (known as the "dead-ball era"). Due to a farm-machinery accident in his youth (April 17, 1888), Brown lost parts of two fingers on his right hand, and in the process gained a colorful nickname. He turned this handicap into an advantage by learning how to grip a baseball in a way that resulted in an exceptional curveball, which broke radically before reaching the plate. With this technique he became one of the elite pitchers of his era.

Brown was elected to the Baseball Hall of Fame in 1949.

Brown was born in Nyesville, Indiana. He was also known as "Miner", having worked in western Indiana coal mines for a while before beginning his professional baseball career. Nicknames like "Miner" (or misspelled as "Minor") and "Three Finger" (or sometimes "Three-Fingered") were headline writers' inventions. To fans and friends he was probably best known as "Brownie". To his relatives and close friends, he was also known as "Mort". His three-part given name came from the names of his uncle, his father, and the United States Centennial year of his birth, respectively.

According to his biography, he suffered two separate injuries to his right hand. The first and most famous trauma came when he was feeding material into the farm's feed chopper. He slipped and his hand was mangled by the knives, severing much of his index finger and damaging the others. A doctor repaired the rest of his hand as best he could. While it was still healing, the injury was further aggravated by a fall he took, which broke several finger bones. They were not reset properly, especially the middle finger (see photo).

He learned to pitch, as many children did, by aiming rocks at knot-holes on the barn wall and other wooden surfaces. Over time, with constant practice, he developed great control. As a "bonus", the manner in which he had to grip the ball (see photo) resulted in an unusual amount of spin. This allowed him to throw an effective curve ball, and a deceptive fast ball and change-up. The extra topspin made it difficult for batters to connect solidly. In short, he "threw ground balls" and was exceptionally effective.

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