Clarke was born in Winterset, Iowa. He joined the Louisville Colonels in 1894 and, in his second season, 1895, asserted himself as one of the team's best hitters, batting .347. In 1897 Clarke took over managerial duties, although the team struggled under his guidance for several years.
Template:MLB HoF In 1900, Clarke joined the Pittsburgh Pirates as a player and manager, roles he would embrace until his retirement in 1915. He finished his career with a .312 batting average and having led his team to four World Series appearances (1901, 1902, 1903 and 1909) and one championship (in 1909). The 1903 Pirates lost only 36 games under his guidance, a modern-era record.